Cost per Flight Hour of Military Aircraft

Greetings everyone .

Whenever i read about military plane procurements especially fighter aircrafts, be it in military forum or magazines .. i'm always found a variable called "Cost/ flight hour" or sometimes called as "DOC (Direct Operating Cost) per flight hours" .. and some comparisons ..like say.. F-15 has DOC/flight hour of xxxx U$ much cheaper than other planes.

Now my question is "How this costs is calculated ?"

As far as i can found in Literature ..the only method i can found to calculate that "cost/flight hour" is for Commercial airliners.

Well any suggestions or hopefully good books would be appreciated

It is the combination of fuel burned and the ground maintainence time per hour of flight.

A real example is the Mig-21 costs about $6,000 per flight hour. This is because parts are cheap and plentiful and maintainence is cheap and easy.

More modern aircraft have internal diagnostic systems and testing systems that will not only generate a little report saying what is working and what isn't, but the new systems will actually shut down a system with a problem and bypass the data going to that component to another system to try to do the job.

Prices will also change due to sanctions like Venezuelas F-16s, and of course as technology moves on the older stuff becomes harder and harder to get, which also means more expensive.

For instance... try to get a video tape recorder now... not as easy as one would think... or try to buy a 5 1/4th inch floppy disk.
A Mig-29 from the mid 1980s might need its software on a floppy disk that costs $10 a disk now even though it is completely obsolete for data storage.

Neither Russia or America can afford people....people are needed to support military hardware. China's got the best cost-per-flight-hour formula now. They can afford people.

That's what the formula is all about.

The aircraft with the worst cost-per-flight-hour= B-2 Spirit Bomber.

You could say it was the biggest blunder of any military aircraft that will ever, ever be built (unless they declassify the other accident of a classified airframe).

---it's blueprints were handed to China and other countries by Noshir Gowadia, the Indian engineer Northrup hired to work on it.

---the B-2 crash on Guam...plane belly flopped 100% intact smack dab in the middle of the airfield. Nothing salvageable. Burnt for 6+ hours before Guam Fire Department got there to put it out.


Which is why America's going unmanned remote control or artificial intelligence smaller cheaper airframes. Can't afford people.


In some countries if a pilot lands his fighter plane or bomber with the wheels up, damaging the plane trying to land it...the Wing General will go out and have a talk with him. If he figured out it was pilot error, he breaks out his sidearm and places a bullet into the pilots brain. Some countries will let idiots like that just keep flying and crashing.....case in point...John McCain. Now he's a big famous politician. He only got away with continuos crashing of airframes because of Daddy being a high ranking Naval Officer.

Pervius wrote:

Neither Russia or America can afford people....people are needed to support military hardware. China's got the best cost-per-flight-hour formula now. They can afford people.

And i make my own aircraft concept.. and i need how to calculate DOC.. not Chinese or American stuff.

[quote=GaryB]
t is the combination of fuel burned and the ground maintainence time per hour of flight.

[/quote]

So i can take out Airport Cost and Annual Standing charge eh ..from DOC elements in my spreadsheet ?


Oh BTW here's the screenshot of the excel spreadhseet..hmm sorry its bit un-arranged

Yeah, military airfields don't charge aircraft for operations.

Things that reduce costs include integrated software diagnostics systems that help technicians find and solve problems faster.
Things that are bad are high maintainence things like surface coatings... on a normal plane you undo the screws and take panels off to access the internals of an aircraft.
In a stealth plane you remove the stealthy coating and tape and other things covering the screws, then undo the screws and remove the panel... fix the problem and then put it all back on including tape and surface coatings... real pain and very expensive too.

This is a preliminary attempt to establish some facts regarding the actual costs (CPFH -Cost Per Flight Hour) of operating modern fighter jets.

I have to say in advance that this is a difficult topic, due to several factors:

- It is very difficult to get actual information from different planes and operators. In fact there is almost nothing I can find about Russian planes, so I have to limit this analysis to Western ones.
- Even for the same plane, the costs are very different depending on the user, squadron, specific utilization conditions, age of the fleet, etc.
- The accounting process for the different components of cost is rather complex and variable depending on each operator.

I will try to point to different sources and make a small analysis based on what can be concluded from them. Anybody having solid / sourced information about this topic is welcome to post it here, so that we all can learn from it!

Sources

- US report about the rates that apply of their different aircraft, 2018:

https://comptroller.defense.gov/Portals/45/documents/rates/fy2019/2019_b_c.pdf

- IHS Janes analysis is by far the best source I have found for non-US fighter and I broadly agree with their conclusions too.

https://www.ftm.nl/upload/content/files/IHS%20Jane%27s%20Jet%20Operating%20Costs%20White%20Paper%20FINAL%2013th%20March%202012%281%29.pdf

- RAND analysis explains how the different factors of CPFH are accounted for... if you suffer insomnia this will help  

https://apps.dtic.mil/sti/pdfs/AD1000756.pdf

- Leaked report from the Swiss military about Rafale, Gripen etc. was referred in the forum as containing damning information against the operational costs of the Gripen. I have found nothing like that in the report:

https://de.scribd.com/doc/81390363/Swiss-Air-Force-Confidential-Report-on-the-Evaluation-of-the-Eurofighter-the-Gripen-NG-and-the-Rafale

Analysis based on available data for Western fighters

There seems to be indeed a broad relation between weight of the fighter and its operational costs. I just used empty weights of modern western fighters and their CPFH as taken either from Janes or from official data. No trick needed to plot a trend, but also big exceptions are to be found (especially with the F-18, maybe USN does things differently to USAF?)



The result goes in line with Janes report, which I ultimately recommend reading and think it can be a very reasonable first approach to the issue.

Are single engine fighters proportionally cheaper than twin engine planes?

Difficult to say, given the huge differences even between different squadrons in the same air force. Janes seems to think that to be the case:

Increased CPFH of twin engine aircraft is attributable to factors other than increased fuel usage (est. ~25%)

What indeed seems proven is that very light and basic planes are much cheaper than big and complex ones, the later being normally twin engine while the former being single engine. Logic says more pieces to be maintained (engines are the most maintenance intensive item on any plane) means higher costs, but by how much? A single-engined fighter can have an engine interval between overhaul of only 500 h while a twin engined fighter can have engines that only need a 1000 h interval, for instance. Again, the devil is in the details.

Eastern vs. Western planes

There seems to be a substantial difference between East and West regarding the maintenance costs of their fighters, maybe due to structural differences between their respective economies. The problem is that I have found lots of rumours but no official data:

- Tarasenko from MiG said in 2019 that MiG-35 would be 20% cheaper over its life cycle than its competitors in the Indian MMRCA 2.0 competition:

https://www.financialexpress.com/defence/indias-old-friend-russia-offers-to-transfer-technology-and-produce-mig-35-in-india-mig-ceo/1590224/

- There are references to MiG-29 having an operational cost of $4500 per hour, but how then MiG-35 has reduced that 2.5 times?
- JF-17 is rumoured to have hourly costs of just $4000
- MiG-21 was also referred as having ridiculous operational costs and being extremely simple and sturdy:

The MiG-21 has been called the AK-47 of airplanes. “Rock-solid airframe,” noted a former MiG 21 ground technician. “Really the thing only needs to be topped off with fluids and it just goes and goes.” When the U.S. Air Force operated MiG-21s as adversary aircraft combat trainers, they found them to be, in the words of one crew chief, “Just like your family car. As long as it’s full of fuel, you pull it out of the garage and start it up.” Maintenance typically consisted of changing the oil, brakes and tires after every 50 sorties. “With a set of home socket wrenches and screwdrivers, you could get a lot of maintenance done on the little jet,” said another crew chief. Even more important is the fact that a MiG-21bis can be had for $500,000. A secondhand F-16C can cost a small country $15 million.

https://airpowerasia.com/2020/06/16/the-iconic-mig-21-great-design-most-produced-supersonic-jet-fearsome-reputation-unending-service/

- As a way of checking what the operational costs of Russian air force can be, we know that there are (or rather were?) flights available to individuals, for a "reasonable" price. These flights are 30 min long and include interpreters, hotel nights and many other things, and the prices would be influenced not only by flight costs but also demand, but at least they can be used to find an upper limit for the cost of the flight hour, if we assume Russians would not bother organizing them to loose money. These were the costs per person as of 2012:

Su-27: $17,700.00
MiG-29: $14,000.00
MiG-23: $8,690.00
L-39: $3,100.00

http://rusadventures.com/tour17.shtml

I think we can reasonably assume CPFH would not be more expensive than this, since:

- There is a substantial overhead in these costs due to all the additional expenses for the activity
- The flight is pretty intensive in acrobatic manoeuvres which are tough on the engines and fuel consumption
- I doubt a little more fuel could be so expensive for VKS to seriously distort the figures.

Actually it is likely that they are substantially cheaper, but I didn't manage to get better data. Maybe I try with searches in Russian, I didn't do that yet.

Hope somebody finds this interesting, I will post further data if I find them. And if anybody has better information, you are welcome to share it  

It is off topic but one of the biggest reductions in operational costs for the MiG-29 was when they changed their maintenance procedures from communist to non communist so to speak.

For the Soviets the cost of maintenance was less important, and needing large numbers of men to maintain a plane or long hours were not a problem... the focus was that for 500-1,000 hours you just fill up the things that needed filling and got in and flew the plane without needing any checks or tests and without needing a university degree.

That meant during a war or conflict all the aircraft not in overhaul would be available and ready to go.

Obviously that came at a price.

Maintenance was strict and very safe in regard to tolerances, so for instance during testing it was found that 15 parts of an engine had wear and while each would wear out at a different rate the idea is that between overhauls there needed to be no testing or expert analysis of parts or components...

This meant that for a given engine one of the parts might last 2,000h before needing replacing and another part might need to be replaced every 2,500h, and 7 parts might need replacing every 2,000 to 3,000 hours depending on how the engine in used, and another 5 parts might need to be replaced after between 1,500 and 3,000 hours also depending on how the aircraft is flown.

To be safe then the overhaul and replacement schedule would be 1,000 hours... all the parts that can wear out are replaced every 1,000 hours.

That is very wasteful of parts and also means stripping down engines every 1,000 hours so it takes time but it means in a combat situation you only need to worry about battle damage.

Parts that might be perfectly fine were discarded.

The maintenance of the MiG-29 dramatically got cheaper with portable scanning equipment and onboard diagnostic equipment that would tell the ground crew if there was an electronic problem... computers and computer networks can have problems too of course... it is not just the engines.

The point is that once they started changing the maintenance policy for peace time costs then the requirements for the support crew increased... they needed to be able to use portable scanners to detect cracks in engine blades, and parts started to get replaced only when they actually needed to be replaced.

One thing that has not changed is that Russian pilots are not expected to "go easy" on the planes.

In the west there are limits to manouvers and speeds and altitudes etc that aircraft can be used to prevent excessive wear and tear on the aircraft and their engines.

Regarding that report about the Gripen... it repeatedly says it lacks the range and performance for their needs.. being the only single engined aircraft in consideration, that is no huge surprise.

On page 14 it mentions Saab recommends spare parts pooling amongst all users to keep down costs... reliability or availability the Gripen scores better than Eurofighter...

The fact that in pretty much every area the Rafale was best, Typhoon was second, and both were better than the base standard F-18 they currently operate and that the Gripen rated worse than the F-18 in every regard... even after being upgrade to its latest model type suggests that single engined fighters are also less capable than twin engined fighters perhaps?

There is nothing in that document even mentioning operational costs, so perhaps it was another report... or another part of the report that perhaps SAAB managed to block the public release of...

GarryB wrote:To be safe then the overhaul and replacement schedule would be 1,000 hours... all the parts that can wear out are replaced every 1,000 hours.

Well that seems a good strategy for wartime operations. It is even better if you can harmonize the life of the different parts, so you don't overspend in those that are always discarded even when in perfect conditions. What they have done is rather to improve those parts more exposed to wear, probably they have improved considerably their temperature tolerance. The new RD-33MK for instance has an operational life of 4000 hours and overhaul every 1000 hour, vs. 1600 and 800 respectively for the conventional RD-33.

That alone should be substantial reduction in operational costs: 4000 / 1600 = 2.5, that is most probably the main reason behind that now famous claim of MiG-35 being 2.5 times cheaper. What we don't know is how much cheaper the regular RD-33 is compared to the MK...

The maintenance of the MiG-29 dramatically got cheaper with portable scanning equipment and onboard diagnostic equipment that would tell the ground crew if there was an electronic problem... computers and computer networks can have problems too of course... it is not just the engines.

Electric and electronic problems can be a pain in the *** if the technician is not quite competent (always difficult for complex systems) or lacks the equipment, in which case you just exchange everything, even when you don't know why, but cannot loose one week to diagnose a pathological case... but don't ask about the cost of the repair! Failures are always situations where systems don't do what they should and therefore tend to be quite "creative" and very time consuming to diagnose.

That lack of complex systems is why the MiG-21 was dirt cheap and could be repaired in field with screwdriver and hammer, but no modern plane is ever going to be "affordable"  

The point is that once they started changing the maintenance policy for peace time costs then the requirements for the support crew increased... they needed to be able to use portable scanners to detect cracks in engine blades, and parts started to get replaced only when they actually needed to be replaced.

Now with Su-57 they will be even more extreme, with that fiber optics system to diagnose the stress in the airframe, or those portable hangars to check the stealth coatings.

Regarding that report about the Gripen... it repeatedly says it lacks the range and performance for their needs.. being the only single engined aircraft in consideration, that is no huge surprise.

Well, it is hardly surprising that it has lesser capabilities than the two other. The plane is extremely small compared to the other two, how should it do the same? If they compared Rafale to Su-57 or F-22, it would also look a shitty plane... it depends on what requirements they have. So, if you try to set up a fighter force just based on one single platform, it is good that you don't go for the absolute smallest plane possible. If you have a heavy fighter taking care of the missions that demand range, payload and most powerful systems, then you can allow yourself to make up numbers with way cheaper platforms, 2:1 light : heavy seems to be the ideal proportion. What happens with European air forces that didn't have the money to develop a two-level fighter fleet (and they even split efforts instead of working together) is that they tried to solve everything with medium fighters with the price of heavy ones but without their capabilities, and ended up with very reduced numbers, because they didn't have the cheap light fighters to fill the gaps... a massive flop if you ask me...

The fact that in pretty much every area the Rafale was best, Typhoon was second, and both were better than the base standard F-18 they currently operate and that the Gripen rated worse than the F-18 in every regard... even after being upgrade to its latest model type suggests that single engined fighters are also less capable than twin engined fighters perhaps?

Hahaha, nice try  

It is only logical that the Rafale came on top of that competition, since it is a modern fighter, very well conceived, and designed specifically as multirole (omni-role they say), which was what the Swiss were evaluating. The Eurofighter is not multirole (BTW the report confirms cruise 1.4 M, which is a serious capability for air superiority) and the Gripen in simply tiny, it cannot carry the same fuel or the same payload, and logically in some aspects it will be even worse than the old F-18. It rates high in EW for instance, and they say that many of the improvements that Saab reported were not accepted because they needed capabilities which were current. Those capabilities were going to come at the expense of more weight and a more powerful engine. As said:

1. You can create a plane, single engine or twin engine, with roughly the same TWR. Or at least I don't see a proof of the contrary. If you put two engines side by side you get more thrust but also more drag, in a single engine the same thrust will result in a longer aircraft but also a less draggy airframe. That explains perfectly the respective characteristics of F-16 and MiG-29 that we have discussed. The first is excellent in energy conservation (very low drag), the other in climb and turning rate (thrust and lift at the expense of more drag). Which one is better? It depends on what you want, but for a small multirole plane the first approach makes more sense to me.

2. A light fighter needs to have simpler requirements compared to heavier ones. It is not a fault of the Gripen to be small and relatively simple, it is simply wishful thinking on the part of Switzerland to hope for medium or heavy fighter performance for the cost of a light one...

There is nothing in that document even mentioning operational costs, so perhaps it was another report... or another part of the report that perhaps SAAB managed to block the public release of...

They were actually quite pissed off with the French for getting this released just when their plane had been selected... I don't think they had the release of these documents under control at any time

Well that seems a good strategy for wartime operations.

When you produce the spare parts and you want work for your people then it is good, but many aircraft spend 99% of their time in peace time and it makes it rather inefficient, and also makes it less desirable to more sophisticated countries who dont want simple and cheap.

When the parts you are throwing out after 1,000 hours contains complex titanium parts worth tens of thousands of dollars it is more of a problem... though they might be lasting 4,000 hours so you might save money by replacing them after every third overhaul...

It is even better if you can harmonize the life of the different parts, so you don't overspend in those that are always discarded even when in perfect conditions.

Or perhaps instead of discard, you inspect and analyse and repair if possible for reuse.

That lack of complex systems is why the MiG-21 was dirt cheap and could be repaired in field with screwdriver and hammer, but no modern plane is ever going to be "affordable"

The attempt of the F-16 was supposed to make things easier with modules, with modern computer systems where parts are added and removed, where software updates can fix problems and create more, or simply make the whole system stop working. The same problem is creeping into motor vehicles... John Deer make tractors but wont share information about their software and diagnostic systems, so if something is not working you have to send it to them to fix. Most of the time a laptop and a few minutes might find something is set up wrong or some component has failed, or is broadcasting rubbish which means other things are not working properly either.

I remember when installing a computer game on an IBM type computer meant low level access to all sorts of things you don't worry about now... the operating system handles IRQ channels and sound card settings and the like. Back then the operating systems let you access the hardware directly and set ups could be stuffed up pretty easily. Newer OS manage that sort of thing themselves meaning vastly fewer blue screens...

Well, it is hardly surprising that it has lesser capabilities than the two other. The plane is extremely small compared to the other two, how should it do the same?

But hang on... you are saying that a single engined fighter is better than a twin engined fighter because it is lighter and smaller and cheaper... why are you also not saying that it is less capable and with much reduced performance?

is that they tried to solve everything with medium fighters with the price of heavy ones but without their capabilities, and ended up with very reduced numbers, because they didn't have the cheap light fighters to fill the gaps... a massive flop if you ask me...

So what you are trying to argue is that the Gripen should be bought in addition to either the Rafale or the Typhoon and used together by the air forces of Europe, because while it is not as good as either aircraft in most parameters, it is cheaper.

What would happen if we adopted that concept in other places... this doctor is a woman... she is smaller and lighter and cheaper to pay than the male doctors... she is not as good but we can afford to have more of them... even if they are incompetent...

It is only logical that the Rafale came on top of that competition, since it is a modern fighter, very well conceived, and designed specifically as multirole (omni-role they say), which was what the Swiss were evaluating.

The Gripen is a modern fighter and we are talking about an upgraded model with over 90 changes from the standard model... was it poorly conceived... was it intended to replace lollypop ladies helping children across the road instead of being a modern fighter aircraft?

The Eurofighter is not multirole (BTW the report confirms cruise 1.4 M, which is a serious capability for air superiority) and the Gripen in simply tiny, it cannot carry the same fuel or the same payload, and logically in some aspects it will be even worse than the old F-18. It rates high in EW for instance, and they say that many of the improvements that Saab reported were not accepted because they needed capabilities which were current. Those capabilities were going to come at the expense of more weight and a more powerful engine.

But you go on to complain that the Eurofighter and Rafale are bigger heavier aircraft... their two engines means they should be high drag and therefore lower performance than the smaller lighter Gripen, but that is clearly not the case.

I am quite a big heavy person but I don't work out, I don't have powerful muscles, but I have experienced situations where a strong wind was blowing and smaller lighter people were having difficulty standing up... they ended up walking behind me.  Size has advantages.

Or at least I don't see a proof of the contrary. If you put two engines side by side you get more thrust but also more drag, in a single engine the same thrust will result in a longer aircraft but also a less draggy airframe.

Yes, but what is the value of that drag reduction... none of these planes are bricks... and I would suggest their extra size and weight actually make them rather more effective platforms. Small size has a value, but not at the cost of serious loss of performance...

That explains perfectly the respective characteristics of F-16 and MiG-29 that we have discussed. The first is excellent in energy conservation (very low drag), the other in climb and turning rate (thrust and lift at the expense of more drag). Which one is better? It depends on what you want, but for a small multirole plane the first approach makes more sense to me.

In training with German MiG-29s the F-16s lost every time... they didn't have AMRAAM and R-73 was, together with its helmet mounted queing system, a vastly superior missile to the then standard Sidewinders. The difference in drag was irrelevant... the extra fuel the MiG can carry compensated for the extra drag, and in terms of flight performance the body lift from the twin engine trunks effectively forcing air flowing over the body of the aircraft and generating extra lift gives it advantage in manouver and cruising.

2. A light fighter needs to have simpler requirements compared to heavier ones. It is not a fault of the Gripen to be small and relatively simple, it is simply wishful thinking on the part of Switzerland to hope for medium or heavy fighter performance for the cost of a light one...

So small cheap fighters are shit fighters.... so why bother with cheap when it will also be ineffective?

Sounds like the Heavy (Su-35/57) and Medium (MiG-29M2/-35), with cheap drones (S-70 and others) is a better solution than single engined light fighters.

GarryB wrote:Or perhaps instead of discard, you inspect and analyse and repair if possible for reuse.

If you have the means and the time, of course.

Newer OS manage that sort of thing themselves meaning vastly fewer blue screens...

Electronics and SW are here to stay and for very good reasons, I am not going to question that. It does not mean that they are always going to be applied in the way which is best for reliability, or that they do not need lengthy debugging like happened with the maintenance system on the F-35. The problem with such systems is they are black boxes and without the right knowledge there is nothing a regular technician can do on them.

But hang on... you are saying that a single engined fighter is better than a twin engined fighter because it is lighter and smaller and cheaper... why are you also not saying that it is less capable and with much reduced performance?

I just agree on the concept of hi-lo mix where there are proper heavy fighters in moderate numbers and numerous fighters which are optimized for cost.

So what you are trying to argue is that the Gripen should be bought in addition to either the Rafale or the Typhoon and used together by the air forces of Europe, because while it is not as good as either aircraft in most parameters, it is cheaper.

See above, they should have something bigger than Rafale or Eurofighter and then something like F-16 or Gripen. With heavy planes doing the long range air superiority missions, the smaller ones would not need to be over-stuffed with pods, CFTs and systems that make them partially loose their original sense. It is an issue of flawed force planing, due probably to financial constraints. Instead of assuming high up-front costs, dilute them along many years with modernizations and upgrades to planes that, like it or not, are seriously restricted by their airframe.

The Gripen is a modern fighter and we are talking about an upgraded model with over 90 changes from the standard model... was it poorly conceived... was it intended to replace lollypop ladies helping children across the road instead of being a modern fighter aircraft?

It has a very sound aero design, but was made to meet Swedish requirements. And with its size it will obviously be hampered to have big persistence, do multiple passes on a ground target etc. Every job has its right tool and not everything needs the ultimate super expensive one.

BTW this graphic is coherent with what I said, smaller size leads to disadvantages on persistence, detection range and some others. At a fraction of the operational cost and with the right backing it may be a sound decision to use it though:

their two engines means they should be high drag and therefore lower performance than the smaller lighter Gripen, but that is clearly not the case.

Never said that

and I would suggest their extra size and weight actually make them rather more effective platforms.

I said as much... in fact I think they should be bigger!

Small size has a value, but not at the cost of serious loss of performance...

It is going to mean loss of performance in several areas. As said the whole discussion has an economic background. Air forces have discovered that they can fulfil their missions with a cheaper mix of assets. You can see the numbers of heavy and light fighters most air forces have. Many countries still getting things done with MiG-21, MiG-23, JF-17, J-10, F-16, Mirage etc etc. Do you want to check the numbers? I am not making this up, it is a simple reality of the kind of compromises air forces choose to do.

In training with German MiG-29s the F-16s lost every time... they didn't have AMRAAM and R-73 was, together with its helmet mounted queing system, a vastly superior missile to the then standard Sidewinders.

... which has nothing to do with the different layouts and propulsion concepts

The difference in drag was irrelevant...

Well it is not, each one used their advantages. This chart may well reflect the situation with those two planes, in a very simplified way:

the extra fuel the MiG can carry compensated for the extra drag,

That was one its main problems, it had very little fuel... as said before, its role was quite narrow as a point defence fighter with focus in TWR and manoeuvrability in a short fight at the expense of pretty much anything else. With the new family of MiG-29 they have been smart to expand the roles of the plane and give it more fuel. We don't have critical values like empty weight though, we would need them to compare its current performance

and in terms of flight performance the body lift from the twin engine trunks effectively forcing air flowing over the body of the aircraft and generating extra lift gives it advantage in manouver and cruising.

It is not really clear it has an advantage across the board, it may be better in some low speed manoeuvring (twin keels) but it has worse L/D than the F-16 and that affects the way it can keep speed during combat.



Excess power of the F-16 while turning is outstanding:



If you want to go into the details of comparing F-16 and MiG-29 I think we can do it, since there is a lot of information about those planes available, including flight manuals, EM charts and so on. Some calculations are needed though, since altitudes and fuel weights need to be accounted for and are not always the same for both in the charts.

My point was that the layout of the F-16 is more suitable for a general purpose fighter than a very specific one like the original MiG-29 as it is more efficient. Today's requirements include high AoA performance which means two vertical stabilizers and stealth so the layout would not be directly applicable and the size should grow a bit, but it is still a good example of a very well optimised plane that performs well on many missions.

Sounds like the Heavy (Su-35/57) and Medium (MiG-29M2/-35), with cheap drones (S-70 and others) is a better solution than single engined light fighters.

That is probably what is going to happen in Russia, but that is easy to predict, since those are the planes that they have. It does not mean other solutions may be even better, if Russia had not already invested their resources on the MiG-29 and the "industrial ecosystem" around it. At some point they decided to change from single engine (MiG-21 - MiG-23) to twin engine (MiG-29) for the short ranged fighters too and that of course has an impact on what is available today to work with.

BTW back to the thread's topic, did you read the cost analysis by Jane's? Do you basically agree with their conclusions?

The other issue is that there are no standard methods in the first place. CPFH equations for one nation may not necessarily applicable to the other. Thus making it very difficult to actually see "pattern" in the value of CPFH.

Stealthflanker wrote:The other issue is that there are no standard methods in the first place.  CPFH equations for one nation may not necessarily applicable to the other. Thus making it very difficult to actually see "pattern" in the value of CPFH.

Of course, not every manufacturer wants to deliver data, air forces calculate differently etc etc etc. We can only gather information and see if there are trends. With the existing data, I think it is rather reasonable to take the values from the same service, as those we have from USAF. And hope that the guys from Jane's did a good job and their figures are more or less justified, I cannot interrogate air force bosses to get better numbers...

BTW this graphic is coherent with what I said, smaller size leads to disadvantages on persistence, detection range and some others. At a fraction of the operational cost and with the right backing it may be a sound decision to use it though:

Yeah, but looking at that chart I see three different aircraft... the light one with one engine might be cheaper, but doens't come close to the performance of the bigger twin engined aircraft which seem to be rather more competitive where each is better than some things than the other... we don't see that competitiveness of the smaller cheaper one.

What you fail to prove is that a single engined Gripen is better than a twin engined aircraft also intended to be a cheap light fighter...

Never said that

So there is no advantage to single engine design?

I said as much... in fact I think they should be bigger!

Fitting two engines makes them bigger doesn't it?

Many countries still getting things done with MiG-21, MiG-23, JF-17, J-10, F-16, Mirage etc etc. Do you want to check the numbers? I am not making this up, it is a simple reality of the kind of compromises air forces choose to do.

Yeah, but how many of those countries got a real honest choice as to which aircraft they could buy in the first place?

... which has nothing to do with the different layouts and propulsion concepts

But you are claiming single engined fighters are smaller and more agile and cheaper... if they get shot down then it wont matter how cheap they were.

That was one its main problems, it had very little fuel... as said before, its role was quite narrow as a point defence fighter with focus in TWR and manoeuvrability in a short fight at the expense of pretty much anything else. With the new family of MiG-29 they have been smart to expand the roles of the plane and give it more fuel. We don't have critical values like empty weight though, we would need them to compare its current performance

So you are saying it is worse but you don't know....

It is not really clear it has an advantage across the board, it may be better in some low speed manoeuvring (twin keels) but it has worse L/D than the F-16 and that affects the way it can keep speed during combat.

It lost every engagement against an early model basic unupgraded German MiG-29...

Excess power of the F-16 while turning is outstanding:

But not outstanding enough to win in testing.

If you want to go into the details of comparing F-16 and MiG-29 I think we can do it, since there is a lot of information about those planes available, including flight manuals, EM charts and so on. Some calculations are needed though, since altitudes and fuel weights need to be accounted for and are not always the same for both in the charts.

The comparisons were done in the 1990s by HATO and the solution was that the F-16 got helmet mounted sights and BVR missiles and were not allowed to get close to MiG-29s in combat...

My point was that the layout of the F-16 is more suitable for a general purpose fighter than a very specific one like the original MiG-29 as it is more efficient. Today's requirements include high AoA performance which means two vertical stabilizers and stealth so the layout would not be directly applicable and the size should grow a bit, but it is still a good example of a very well optimised plane that performs well on many missions.

You can try all you like to sell the F-16 but the Russians have said the new light 5th gen MiG fighter will be a twin engined aircraft.

At some point they decided to change from single engine (MiG-21 - MiG-23) to twin engine (MiG-29) for the short ranged fighters too and that of course has an impact on what is available today to work with.

They could go back to flint lock muskets to see if they could improve their performance to modern levels by why go backwards?  

BTW back to the thread's topic, did you read the cost analysis by Jane's? Do you basically agree with their conclusions?

No... I am sorry, but I find such stuff tedious and often framed to promote their favourite product at the time... you don't want to just piss away money for nothing, but the twin engined MiG is cheaper to operate than the twin engined Flankers and really that is all that matters.

Of course, not every manufacturer wants to deliver data, air forces calculate differently etc etc etc. We can only gather information and see if there are trends. With the existing data, I think it is rather reasonable to take the values from the same service, as those we have from USAF. And hope that the guys from Jane's did a good job and their figures are more or less justified, I cannot interrogate air force bosses to get better numbers...

The problem is that different ideas about supporting aircraft effect the results too much.... the Indians used to complain about the serviceability of Russian planes, but that was mainly because they ordered parts when they needed them... and all the red tape and crap meant it could be a while to get them.

Politics in an air force is a thing too... some airfields getting better support or higher priority than others.

Plus the US can't do affordable.

GarryB wrote:Yeah, but looking at that chart I see three different aircraft... the light one with one engine might be cheaper, but doens't come close to the performance of the bigger twin engined aircraft which seem to be rather more competitive where each is better than some things than the other... we don't see that competitiveness of the smaller cheaper one.

If you can buy and maintain two or three for the price of one of the others it would still be an attractive plane.

The diagram is a bit cryptic in terms of manoeuvring combat for instance, there is one "aircraft performances" axis and then an "engagement" axis in which we don't know exactly how and what is evaluated. I think it is fairly reasonable to think a small, light plane with little dead weight (small airframe and fuel tanks) has some advantage in manoeuvrability and acceleration, also visual footprint is relevant in combat. But the diagram does not explain much in that regard.

What you fail to prove is that a single engined Gripen is better than a twin engined aircraft also intended to be a cheap light fighter...

When did I say something like that? Somebody claimed the Swedes had lied regarding the operational costs of the Gripen and I found out the referred report said nothing of the like. The day I say a small cheap fighter is better in absolute performance than a heavy expensive one you are authorized to shot me and spare me the suffering  

If Jane's values are true and Gripen costs 5 k to operate vs 18 k on the Eurofighter for instance, then the whole argument "which is better" is pointless.

So there is no advantage to single engine design?

Why are you trying to make this a matter of black or white? You know aircraft design is a matter of compromising. I stated some natural consequences of the single vs twin engine on the general shape and characteristics of the airframe, not claimed one to be superior above the other.

I will try again:

- If you have twin engines side by side, you place mass and drag in parallel with the planes longitudinal axis, since two engines are wider and shorter than one of the same thrust. Agree?
- You get more drag for the same thrust with that design, but also a shorter airframe that may be lighter and hence have some other advantages associated to it, like lower pitch moment.

Here it is easy to understand why a fighter like the MiG-29 has a short and wide fuselage, high TWR and low fuel. It was designed for being capable to keep up or defeat F-16 and F-15 in close combat. Its design characteristics were not specially good for range. In combat, it has worse energy conservation than the F-16, which is also easy to infer from both plane's design characteristics and fully consistent with the data I provided. Each approach has its pros and cons.

And to make my take on the single vs. twin engine clear:

I think single engine makes more sense in the very particular situation where you already have a heavy twin engine air superiority fighter and you are going to create the lo part of the mix, since it allows two things which are important IMHO:

- Economies of scale and ease of maintenance due to the fact that both aircraft share the same engine;
- Complementarity between the characteristics of those two planes: one should have long range, big payload and powerful systems & avionics while the other should be very agile, simple, cheap to operate and numerous. One would control the BVR combat while the other would be a plane the enemy does not want to meet at close quarters. Different propulsion and aero layouts contribute to this complementarity too.

Fitting two engines makes them bigger doesn't it?

They should be full blown heavy fighters, not half arsed hopeless attempts at making a big plane that costs like a small one.

So you are saying it is worse but you don't know....

I am a bit perplexed now... why the reductionism? You know, I like to take data and look at it before saying how good a plane is. In the case of the new MiG-29 generation, they were so nice not to publish empty weights. That is the crucial data they can hide and difficult all the comparative analysis, because it influences everything, wing load, STR, acceleration, climb, fuel consumption and so on. It does not mean that we don't know the F-16 airframe is less draggy in absolute and relative terms, which is also a crucial characteristic for a fighter in all aspects, economy among them. The "lo" side of the mix in a multirole fleet is not there for pure performance but to be a balanced plane that can complement the heavy ones and, very importantly, that can be bought and operated in numbers. No point in trying no make this discussion a matter of good vs evil, I don't see it that way, it is just a matter of optimization and what criteria different people and services have.

It lost every engagement against an early model basic unupgraded German MiG-29...

I can provide also info on that, as well as comments from the pilots dealing with the details of the engagements. In short, in WVR the helmet and missile combo was far superior, not the manoeuvrability or dynamic performance of the plane.

The comparisons were done in the 1990s by HATO and the solution was that the F-16 got helmet mounted sights and BVR missiles and were not allowed to get close to MiG-29s in combat...

Makes a lot of sense, if they felt they had a better BVR package but were not superior in close combat.

No... I am sorry, but I find such stuff tedious and often framed to promote their favourite product at the time... you don't want to just piss away money for nothing, but the twin engined MiG is cheaper to operate than the twin engined Flankers and really that is all that matters.

Ok, it is difficult to form an opinion on the report then, and we don't have much better info than that. As to the costs of the MiG, the reality is that we don't know them, and their leadership's sales pitch "our MiG-35 is twice and a half times cheaper than the MiG-29" doesn't help either. The relevant question is: how much cheaper the MiG-29 would be, if it was single engine? That I would really like to know. Don't you think the reduced maintenance and spare parts burden would help, even when not discussing how relevant in the total CPFH that would be?

The problem is that different ideas about supporting aircraft effect the results too much.... the Indians used to complain about the serviceability of Russian planes, but that was mainly because they ordered parts when they needed them... and all the red tape and crap meant it could be a while to get them.

Politics in an air force is a thing too... some airfields getting better support or higher priority than others.

Plus the US can't do affordable.

Of course. It is also very easy to falsify data for political gain, like when they talk big now about the availability rates of the F-35, without saying how much does it cost to keep them above 80%. I can have 100 guys nursing every plane at an astronomical cost and the warehouse full of pieces that are missing somewhere else, as far as such information is not publicised everything seems ok.

In this annual report of the Swedish armed forces the operational costs of the Gripen can be found.

https://www.forsvarsmakten.se/siteassets/4-om-myndigheten/dokumentfiler/arsredovisningar/arsredovisning-2005/ar05_huvuddok.pdf

BTW: I didn't realize when creating this thread, that Stealthflanker had already done one. Can we merge both?

If you can buy and maintain two or three for the price of one of the others it would still be an attractive plane.

Yes, because having lots of planes is always more effective than having good planes... that is why the Soviets won WWII because they had more Polikarpovs than the rest of the world combined had aircraft.... and it was the same with light tanks... they Soviets had tens of thousands of T-26 light tanks so of course they won WWII, because small cramped two man tanks with poor optics, a good gun, weak armour and no communications is always going to kick the arse of much smaller numbers of German tanks with ordinary guns, ordinary armour, good optics and well laid out crew roles and tactics and excellent communications and training...

I think it is fairly reasonable to think a small, light plane with little dead weight (small airframe and fuel tanks) has some advantage in manoeuvrability and acceleration, also visual footprint is relevant in combat. But the diagram does not explain much in that regard.

The problem there is that both sides had already adopted air defence systems that largely involved large radars being used to detect threats and command structures where interceptors were directed to engage those threats along paths that were the safest for those interceptors to positions where the interceptors could launch attacks on the targets at minimal danger to themselves... directed by AWACS or ground control... where acceleration and manouver don't really come in to it.

By the mid 1990s HATO had had their chance to practise against MiG-29s and R-73s and helmet mounted sights and they realised that dogfighting with the Soviets would be suicide and that launching longer ranged missiles from outside visual range was the way to go because if you got within visual range of the target then that was mutual and if they launched a missile at you before your missile took them out of the fight then there was a good chance you were both walking home... if you survived that is.

Manouver became Typhoon manouver... climb and accelerate and launch and then turn away... old model Sidewinders and their equivalents had narrow fields of view and slow tracking rates and could not turn particularly hard... R-73s and similar later missiles had wide fields of view and fast tracking rates and thrust vectoring engines so they could turn hard and follow even light fighters turning in eye watering turns...

As I mentioned the F-16s they tested against the downgraded export MiG-29Bs used by East Germany that were further lumbered with having to carry the centreline external fuel tank which reduced manouver performance (5g I seem to remember) managed to get on the tails for a shot about 62% of the time... but they didn't win any of the tests because the MiG-29 pilot was ruled in each case to have already taken a shot with their high offboresight R-73s and gotten a kill before the F-16 was ready to fire.

I am not trying to suggest manouver is of no use, but during WWI the game was to get on the targets tail to prevent your enemy from bringing to bare his forward firing guns on you while at the same time positioning your forward firing guns on him... the ideal situation... if your aircraft was more agile than his there are not many manouvers he can perform to get you off his tail... which makes his position dominant.

Right now however, a missile can manouver and cover distance much faster than a plane... so being able to fire a missile forward that turns 180 degrees and comes back at something behind you means your position isn't as dominant... and more importantly pulling back hard on the flight stick to rotate the nose of the aircraft up and over and to end up pointing backwards and then launching a missile that missile will burn all its energy accelerating towards the enemy plane and wont be wasting energy pulling a 180 degree turn in the first few seconds of its flight... the time when it has the most energy it is wasting it on a hard turn...

In WWI such a manouver would be suicide because you can't fire guns forward and have the bullets turn 180 degrees and hit a target behind you, and pulling back on the stick to face backwards would result in a super stall which would make you an easy stationary target and then you would fall uncontrollably... so you stop and drop with no control of where you guns are facing.

Today with thrust vector control engines you can turn your nose to point at the target and keep it there to launch a missile and then point your nose down and fly away in full control.... you will be a stationary target but if you do it when the enemy is 5km away on your tail, your missile should hit him before he gets in cannon range anyway, and you will be directing your nose at the next target to launch a missile at anyway.

The rules of maintaining energy are changed because you don't stall and lose control of your weapons...

If Jane's values are true and Gripen costs 5 k to operate vs 18 k on the Eurofighter for instance, then the whole argument "which is better" is pointless.

But the Eurofighter was never intended as a cheap to operate aircraft so the example is irrelevant... but even if we ignore that... if it takes three Gripens to get the job done then is it really cheaper in actual terms because owning and operating three times more aircraft is not really actually saving much money...

Why are you trying to make this a matter of black or white? You know aircraft design is a matter of compromising. I stated some natural consequences of the single vs twin engine on the general shape and characteristics of the airframe, not claimed one to be superior above the other.

Because you are demanding that the new stealth MiG be single engined because you claim it would make it cheaper aren't you?

- If you have twin engines side by side, you place mass and drag in parallel with the planes longitudinal axis, since two engines are wider and shorter than one of the same thrust. Agree?

I would agree but would argue if the single engine has the same thrust as the two engines in a twin then you have already lost because that single is going to be crap.

To even have a chance of being useful the single has to have at least 3/4ths the power of the two engines combined.... ie MiG-29 with two 8 ton thrust engines vs F-16 with an 8 ton thrust engine? More like 12 ton at the very least...

- You get more drag for the same thrust with that design, but also a shorter airframe that may be lighter and hence have some other advantages associated to it, like lower pitch moment.

Spaced engines also add fuselage lift and torque for roll control using TVC engines... and space for internal weapon bays...

Here it is easy to understand why a fighter like the MiG-29 has a short and wide fuselage, high TWR and low fuel. It was designed for being capable to keep up or defeat F-16 and F-15 in close combat. Its design characteristics were not specially good for range. In combat, it has worse energy conservation than the F-16, which is also easy to infer from both plane's design characteristics and fully consistent with the data I provided. Each approach has its pros and cons.

Every upgrade the MiG has ever had has included improvements in fuel capacity... but I wonder if the F-16 and F-15 are so fuel rich why are both getting conformal external fuel added to their designs?

- Economies of scale and ease of maintenance due to the fact that both aircraft share the same engine;

It is a false economy, because the heavy and light fighters will rarely operate together from the same base so commonality is irrelevant except at the strategic level where having a couple of different engine types is fine... for goodness sake at the moment the Su-27SM, Su-30, Su-34, Su-35, and Su-57 don't use the same engine... it is clearly not critical.

- Complementarity between the characteristics of those two planes: one should have long range, big payload and powerful systems & avionics while the other should be very agile, simple, cheap to operate and numerous.

They can already achieve that with the Su-57 and the S-70 drone combination...

One would control the BVR combat while the other would be a plane the enemy does not want to meet at close quarters.

With modern WVR missiles no one wants to meet at close quarters...

They could fit a Yak-152 with 10 weapon pylons and a helmet mounted sight... it would be smaller than any F-16 or MiG-21... it would be cheap...

They should be full blown heavy fighters, not half arsed hopeless attempts at making a big plane that costs like a small one.

You are the one suggesting that fitting one engine to an otherwise modern fighter will somehow make it cheap and simple.

It is pretty clear the Russians are not interested as they have already stated it will be a twin...

In the case of the new MiG-29 generation, they were so nice not to publish empty weights. That is the crucial data they can hide and difficult all the comparative analysis, because it influences everything, wing load, STR, acceleration, climb, fuel consumption and so on.

They are not obliged to reveal anything at all, but I don't understand why you think a plane with better wing load or STR or acceleration or climb rate or fuel consumption and so on makes any difference at all... the MiG-21 was one of the best examples of light fighters... small light cheap easy to operate and maintain, difficult to see in combat... according to you it would be the ideal replacement for the MiG-29... except it isn't... the MiG-21 design is great for size and cost, but its limit payload and range means you can have a lot, but you need a lot, and in most areas the F-16 is better simply because the MiG-21 was the benchmark that the F-16 design was based on, but that is not to say it can beat every time unless the F-16 has AMRAAMs and the MiG-21 has AA-2s...

The reality is that the air force that operates the aircraft and the missiles it will be carrying and of course training and tactics matter more than fuel efficiency.

I can provide also info on that, as well as comments from the pilots dealing with the details of the engagements. In short, in WVR the helmet and missile combo was far superior, not the manoeuvrability or dynamic performance of the plane.

So as new aircraft will be fitted with WVR missiles and helmet mounted sights doesn't that render agility less useful than altitude and speed?

Makes a lot of sense, if they felt they had a better BVR package but were not superior in close combat.

They didn't, but they didn't appreciate that either...

As to the costs of the MiG, the reality is that we don't know them, and their leadership's sales pitch "our MiG-35 is twice and a half times cheaper than the MiG-29" doesn't help either.

And who do you think they are fooling... the Russian Air Force know what their MiG-29s cost to operate and they know the costs of operating Flankers of all types too.

The relevant question is: how much cheaper the MiG-29 would be, if it was single engine? That I would really like to know. Don't you think the reduced maintenance and spare parts burden would help, even when not discussing how relevant in the total CPFH that would be?

Klimov doesn't have a suitable engine, it would be a pointless exercise... a bit like saying what sort of performance would a MiG-31 have if you take out the two jet engines it has and replace them with a single NK-32 25 ton thrust engine... being a single engined aircraft they could make it so much lighter so the loss of power with the single engine could be compensated by lower drag blah blah blah...

Or how about a twin engined B-52... wouldn't it be so much cheaper and simpler... they could double its range...

The problem is that the Russian Air Force is not interested in manned single engined fighters... as far as I can tell the only single engined aircraft they have are trainers.... Yak-152, L39, and the An-2 transport plane...

Of course. It is also very easy to falsify data for political gain, like when they talk big now about the availability rates of the F-35, without saying how much does it cost to keep them above 80%. I can have 100 guys nursing every plane at an astronomical cost and the warehouse full of pieces that are missing somewhere else, as far as such information is not publicised everything seems ok.

Not new... during Desert Storm there were issues with the availability rates of the Apache helicopters.... the solution was pretty simple... they tripled the budget and man hours in maintenance and the availability rates got close to normal...

BTW: I didn't realize when creating this thread, that Stealthflanker had already done one. Can we merge both?

Make it easier for me with a link....

I got some reasonably reliable reference to the operational price difference between modern Sukhois and MiG-35:

The main difference between the MiG-35 and the Su-30SM and Su-35S generation 4 ++ multipurpose aircraft already in service is efficiency. The cost of its flight hour is about one and a half times lower than that of modern aircraft of the Sukhoi family.

http://redstar.ru/podyomnaya-sila-krylev-rossii/

So CPFH of the MiG would be 2/3 of that of Sukhois. That would be roughly in linear proportion of their MTOW (MiG's is 70% of Sukhoi's)

No reference was done to what factors are considered in this operational cost metric, fuel, pieces, staff etc.

Life cycle costs are from left to right and capability from bottom to top... where the further left you are the cheaper you are and the further right you are the more expensive you are, while lower down the chart is less capable and higher up the chart more capable.

So this chart is showing all the euro canards are ahead of the Su-35 in terms of performance and the Su-35 is more expensive than any of them...

It also makes the claim that the current model Eurofighter Typhoon, the Rafale, and the F/A-18 and the Gripen NG are all cheaper to operate than any model MiG-29 or Flanker... while the F-35 is more expensive than the Fulcrum, but cheaper than any model Flanker and more capable... in fact the only planes more expensive than the Flankers and the Fulcrums is the Su-57 and the F-22.

I am guessing that screen is probably nice and soft three ply to have that sort of shit on there... that is pure marketing bullshit that makes you wonder why they bother.

For instance India will look at that and say... well we got offers for MiGs which are not on that chart an we got offers for the Rafale which would be off that chart.

I would be interested in seeing the figures they used to compile the chart in the first place... the numbers I have heard for Su-35s and Su-57s suggest they should both be to the left of the F-16IN, but of course further forward of where they are in terms of capabilities too.

Makes you wonder how the Russians manage to operate the worlds most expensive fighters on 65 billion a year.

F-22 has no capabilities other than stealth. No ground attack, no antiship, no jamming.

Grippen is just as expensive as typhoon/rafale. Proven during swiss tests leaks. And its a single engine fighter.

Rafale is much better than typhoon and f-18.

F-35 capabilities needs to be on the same level as mig-29S. It can barely carry weapons internally and when put externally it loses its stealth and has no manoeuvrability. Its overall perfs are just as good as a mig-29SMT.

They need a wider board like 10m wide and push the cost of f-22 and f-35 on the far right to respect cost reality.

Rodion_Romanovic wrote:According to this graph the gripen NG has the same operational capabilities of a Su35... did they create the graph after smoking weed and eating hallucinogenic mushrooms?

This is NATO standard political correctness, you must say anything Russians do is always going to be under par. A Western propeller aircraft is better than the Su-35 and the Su-57 may be marginally better, but it will never be produced in numbers etc etc...BS of the highest order, all of it.

I linked it just because it is additional material for the thread and obviously with more value in regard of a comparison between Western fighters than anything else. I think we can perfectly disregard the Russian fighters included in the graph, there is no way they can know Su-57 capabilities and costs for instance.

Isos wrote:Grippen is just as expensive as typhoon/rafale. Proven during swiss tests leaks. And its a single engine fighter.

We saw nothing like that in the report. Please provide the evidence, otherwise I have to consider that claim debunked...

We saw nothing like that in the report. Please provide the evidence, otherwise I have to consider that claim debunked...

Well I checked it wasn't written in the report.

But I remember seeing somewhere that Grippen's cost per hour was 20k instead of the 7k.

Grippen NG will be even more expensive.

However the report confirms it's a shitty aircraft.