F-35 Cancelled, then what ?

[Justanopinion]

10 years relying on the single Pegasus engine in the most demanding environments possible- 0 issues.

2 years flying a twin engine jet- 1 engine fire and one of a similar type
crash due engine perf on take off. (Not me!)

Ill take the single Pegasus thanks

[Easy Street]

I seem to recall that the reason that Harriers weren't allowed to fly over London for fly pasts in recent years was that the risk of engine failure was too high given the chances of landing in a heavily populated area. Not helped by Harriers not gliding very well (JF feel free to comment as appropriate!) No such issues of course for Hawks.

True, but the only Hawks allowed were (and still are) the Red Arrows, presumably because the pilots' exceptional skill and judgement guarantee that they could point the thing safely into the Thames before ejecting after an engine failure. A 'standard' Hawk pilot is not trusted for this purpose!

Seem to remember that engine-related ejection from a Harrier was practically a monthly BTR for a while in the mid-late '90s (although to be fair there were a couple of pilot-induced ones, too).

[WhiteOvies]

Mike - Dornier 31 definately goes in the experimental VTOL pile!

Easy Street - Pegasus had a very FOD sensitive LP1 fan until the design was changed in about 2004. Unfortunately the redesign had a habit of chipping the snubbers when fitted in the FA2 (but not in GR7) which led to further compressor damage.

[JSFfan]

flighthappens,
The F100-PW-229 and graph from RetiredF4 http://www.afsec.af.mil/shared/media...120807-022.pdf and the F110-GE-132 are the latest engines and haven't had an engine crash and is factually right, it was the early enginens that were lawn darts.
ORACused an early engine F-16/F110-GE-129 that has had engine crashes

[Archimedes]

Hang on a minute, JSF Fan - you got the wrong engine. Not ORAC.


You were only dug out of the hole you'd inserted yourself into by the provision of the graphs (which you'd clearly not bothered to explore before your edited post thanking Retired F4).

And instead of doing the simple, straightforward thing - namely going on from thanking Retired F4 and saying something to the effect of 'Sorry, my mistake, it was indeed the Dash 229 I was thinking about', you're instead trying to make out that it was ORAC who was wrong originally. Even if it was necessary to have a pop at ORAC for his rather direct response (as opposed to being thick-skinned enough to let it pass), doing this by trying to make out - twice now - that he was wrong about the engine type beggars belief.

Still, on the bright side, it does at least suggest that you have the required levels of integrity to enter politics...

[Big Pistons Forever]

The math seems pretty simple to me

1 engine fails = 0 engines left

1 of 2 engine fails = 1 engine left

I know what I would prefer.......

[mike-wsm]

Lindy preferred one.

[ORAC]

And Rutan preferred two...

There are many trade-offs to decide if one engine is better than two, the peacetime serviceability rates being only one. Then case was made that, if you did the maths for purchase price, running costs, MLU etc, over the life of an aircraft, that a single engined type was still cheaper even if additional aircraft were lost. However if you were the pilot floating down over the middle of the Bering Sea that might not be of great comfort.

There is also the factor of battle damage. The USN took heed of the number of F-18s which came home in GW1 with damaged tail-pipes and engines against the loses of AV-8Bs - and I am aware that was attributable to the nozzle locations of the Harrier making it susceptible to IR missiles.

I don't believe there is a knockout technical argument on either side. If you have to have VSTOL, then single engine is the only realistic option. If, like Canada, you don't, then it comes down to preference.

Having two engines does bring it's own problems. If you separate them then single engine handling issues, a la the Canberra, can cause losses. If you put them together then the failure of one can take out the other. The F-111 cured that by placing a large, heavy, titanium sheet between them. I saw one that landed at Newcastle with the entire fuselage ripped upon on one side. Impressive that it managed to keep flying.

[Madbob]

Justanopinion

Re. post #464, remember you always also had the option of an MB letdown in your single jet. Not always an option for the rest of us!

One reason why I am sceptical about flying something like a PC12 or a TBM 700/850 or even a Cessna Caravan even though the PT6 is a very reliable engine.....

I know that the F35 has a MB rocket seat but even so I do belive that two engines are better than one. How many Tornado's, F14's, F15's and Buccs (I won't count Jags as their SE performance was marginal at best ) have been saved by having two engines rather than one?

MB

[kbrockman]

an old idea put to new use???

If the Canadians keep their faith in the one engined option and after 'carefull' consideration decide to stay with the F35, because let's be realistic here , it's gonna happen even if the twin engined alternatives are in reality a much better solution, why not go again with a two type fighter force like they (and so many other nations) had before?

A F35 force of let's say 36-48 or so combined with another 36-48 cheaper but almost equally capable light weight fighters might make much more sense economically wise, even if they have to support 2 types iso 1.

F35 for first day war and mainly A2G missions afterwards combined with a more A2A orientated (and only secondary role A2G) F16 or Gripen type of fighter, both of which can be further developped through the V version for the F16 and the NG for the Gripen, might be the only workeable way for air forces like the Canadian ones to get good use out of their F35's.

It would also help with other issues , like the price associated with pilots getting enough quality fast jet time, the F16 and Gripen also come in a 2 seater version which is very valuable for certain training missions and they are top notch enough to fend off almost all threats in their A2A role with (AESA radars, Link16, METEOR for NG gripen, etc... ).

It worked fairly well before and with the price associated with the F35 , certainly operating costs, it might be the best way to keep a credible and (barely) affordable fleet.

This whole idea was vented a couple of years ago by a Dutch retired ex F16 pilot/general and it seemed very logical to me, so again, why not?

[ORAC]

This whole idea was vented a couple of years ago by a Dutch retired ex F16 pilot/general and it seemed very logical to me, so again, why not?

Because the costs of setting up and running two different logistics/engineering support and ground crew/aircrew training systems for the life of the system far exceeds the difference in initial airframe price.

[kbrockman]

Given the very expensive to operate F35 and comparably much cheaper operating costs of both the F16 and Gripen, I wouldn't be so sure about that, each type operating from their home base (Bagotville, Cold Lake, or wherever else) needs a cetain amount of support tied with that base anyway , 2 F35 Bases will inevitabely be much more expensive to run than 1 F35 base and 1 F16/Gripen base.

Over a certain number of fighters it does make sense to buy and operate a fleet of 2 types.
36 of each might be the absolute lowest limit but given the large discrepancy in flightcost per hour it might be worthwhile to consider.

Also don't forget that if they choose the F35/F16 option , they could still be tied on al levels with the USAF, who as things look now, will be operating a substantial amount of F16's and future derivatives for many years to come, just wait and see until january first when sequestration will hit reality.
It is already decided that there will be no massive layoff rounds in the US DoD and the 1.7% payrise will go ahead even if sequestration comes into effect.
The acquisition programs will be hit hardest and the F35 is going to see some massive cuts for both the USAF and US NAVY, that is pretty much a given ,1800 iso 2400 is not impossible, even further reductions are possible.



Just to set things clear, personally I think that a twin engined alternative to the F35 is still a much better option (SH or EF) but I don't think that the powers that be are willing to give up completely on their F35 dream, nightmare or not.

[LowObservable]

Mike-WSM...

Lindy knew that with 1927 technology, engine failure = swimming lesson more or less regardless of number of engines. (The Do X was still on the drawing board.)

Other comments...

Small mixed fleets might not be as silly an idea as they once seemed. As aircraft become more reliable and the global supply chain becomes more efficient (how far am I from a FedEx, even if I'm deployed?) then you should be able to operate with a smaller fixed logistics base (no big warehouses or parts repair) or use a commercial-type base plugged into the global market (see Swiss AF/RUAG).

At the same time, the Intertubez, better relationships with potential coalition partners and the more widespread knowledge of a common language permit collaboration with other small operators.

[ORAC]

As aircraft become more reliable

F-22 perhaps, as the last stealth aircraft?

Maintenance & Readiness: As operational experience has built up, the F-22’s maintenance and operational costs have come under fire. The most celebrated instance involved a July 2009 Washington Post story that gave various details, followed by reports from the USAF that some of the Post’s statistics and allegations were untrue.

Official USAF responses say that maintenance and readiness targets must be met only when the aircraft reaches 1000,000 flight hours, but adds that from 2004 – 2009, F-22 readiness improved from 62% to 70%, while mean time between maintenance rose to 3.22 hours in Lot 6 (FY 2007) aircraft, which is better than the KPP (Key Performance Parameter) goal of 3 hours. Direct maintenance man-hours per flying hour dropped from 18.1 in 2008 to 10.46 in 2009, which is better than the target rate of 12 hours. According to the Washington Post, however:

“The Air Force says the F-22 cost $44,259 per flying hour in 2008; the Office of the Secretary of Defense said the figure was $49,808. The F-15, the F-22’s predecessor, has a fleet average cost of $30,818.”

The USAF responds that USAF data shows that F-22 flight hour costs include base standup and other one-time deployment costs, which the F-15 no longer needs. The USAF says that variable cost per flying hour is a better comparison, and 2008 figures were $19,750 for the F-22 and $17,465 for the F-15. Of course, that’s still higher, and the Raptor program had promised flying hour costs below the F-15.

That reality is not surprising. The F-22’s stealth coatings and tapes are part of this equation, something that has been true for all stealth aircraft to date, and may yet affect the F-35 program as well. Even without the stealth equation, however, every new American fighter for the past several decades has promised lower maintenance costs and higher availability rates than its predecessors – and failed to deliver. In practice, rising complexity means costs are consistently higher, and availability rates consistently lower. That lack of readiness makes the problem of smaller fighter stocks worse, creating an even deeper reduction in fielded numbers.

[Engines]

ORAC and Others,

Just a couple of thoughts on this discussion and especially F-22 operating costs. While it's absolutely true that the LO stuff on F-22 generates additional support costs, the main driver is that the F-22 is a very (very) large, heavy and complicated aircraft.

Two very powerful engines crammed into an airframe that is stuffed with fuel, lots and lots of avionics and four weapons bays results, all being pushed through the air at high speeds and high g means system complexity and lower reliability.

The F-22 is, in my view, the last of the gold-plated 'dinosaur' combat aircraft, where performance requirements were allowed to drive designs well beyond the bounds of affordability. It was the experience of the Raptor programme, plus a slew of other cancelled tactical fighter bomber programmes (all large twin engined aircraft) that led the Pentagon to devise JSF as a single engined design in an effort to control size and costs.

It's clear that F-35 costs have still been allowed to get well out of the box, but holding the aircraft to a single engined design has definitely constrained weight. And in the end, that will help control costs, although probably not as much as the programme's architects hoped.

Oh, and the nozzle positions of the Harrier actually helped against IR missiles, as they were fairly well shielded in many engagement aspects, reducing the chance of IR lock on. The cold front nozzles also helped reduce IR signature and improve the effectiveness of IR countermeasures. I ran a number of trials on IR stuff many years ago and I can tell you that it was conventional jet types like the Tornado that were simply massive IR targets. Of course, as missiles have improved the chances of any jet evading the b***ers has reduced.

Best Regards as ever to all those working long hours to deliver the F-35 to the people at the front line,

Engines

[glad rag]

Oh, and the nozzle positions of the Harrier actually helped against IR missiles

Interesting.

[Engines]

Glad rag,

Good pic and quite consistent with what I said. The Israelis learnt very quickly that exposed tail end jet pipes represented big IR targets. Their very practical response was to extend the jet pipes so that the relatively small warheads then in use would explode further away from the critical bits in the fuselage, blowing off just the aft end of the pipe and increasing their chances of surviving a missile hit.

Skyhawk also had a relatively long jet pipe, which helped reduce the IR signature. Jets with the engines located right at the rear (e.g. Tornado) had, in my experience, simply massive signatures, requiring fairly big (and heavy) flares to offer any real chance of protecting the aircraft.

Hope this helps

Engines

[Thelma Viaduct]

Please can we have more single engine aircraft over London????

[WhiteOvies]

I had always understood that the Harrier nozzles reduced the IR signature too, but we still needed an advanced defensive pod from Terma to operate in the manpad threat in Afghanistan. Tornados had a similar pod fitted when it took over, but in a high speed capable fairing.

The constant drive of evolving threats vs defences which F-35 will have to face throughout its operational life.



Kbrockman - your argument holds true for the RAF with Typhoon and F-35 operating together for the medium term. Also Australia with its Growler and F-35 combination. Canada's options are limited unfortunately.

[LowObservable]

PP - They don't make single-engine Islan ... excuse me there is someone at the door WHAP SPLAT uuurgh.....