What will the Government buy if the F35 is cancelled?

[LukeBird]

Talksteer said:

I suspect the 4.5g sustained turn is probably at something like 30,000ft and Mach 0.9 but without knowing what the parameters are it cannot be compared to any other combat aircraft.

I would be inclined to agree.
But, and it's quite a big but, given how coy Lockheed Martin are being over most of the performance stats, it makes it quite difficult to judge anything of the project at the moment.

[aeropilot]

Talksteer said:

PugwasHDJ80 said:

I'm still stuck on the 4.5g frame limit.

at least the pilots won't need G-suits!

The g limts are 9g, 7g and 7.5g for the A, B and C models.

The 4.5g figure quoted is a sustained turn rate, which is a measure of drag at high angles of attack versus thrust. The F35 has a relatively small wing area and would be expected to bleed off speed quicker than an aircraft with a larger wing.

If that's the case, then why wouldn't the C version with it's bigger wing area have a higher sustained g limit than the A or B....?

[AshVX220]

LukeBird said:

Talksteer said:

I suspect the 4.5g sustained turn is probably at something like 30,000ft and Mach 0.9 but without knowing what the parameters are it cannot be compared to any other combat aircraft.

I would be inclined to agree.
But, and it's quite a big but, given how coy Lockheed Martin are being over most of the performance stats, it makes it quite difficult to judge anything of the project at the moment.

I suspect the performance stats in the public domain are intentional mis-information. Performance of any defence systems are amongst the most classified bits of information, other than a specific piece of technology.

[LukeBird]

Absolutely.
But the information that has been released, has so far made them look a little silly!
Any further information from congress as to whether they're going to give them a kick up the arse?

[shouldbworking]

Are all the weapons it could carry rated to that kind of g?

[Mave]

LukeBird said:

Talksteer said:

Interesting g stuff

All very well, but the two comparisons you have used are an F-4 and a very early F-16; the F-35 should be considerably beyond either of those for performance.

Why? The requirements were for legacy levels of A/A performance. It's not intended to be an air superiority fighter......

[Mave]

shouldbworking said:

Are all the weapons it could carry rated to that kind of g?

Oh yes.

[Mave]

davepoth said:

Mave said:

I think that this was to establish the shock wave properly on the intake cone, to get more power out of the engines? They intakes were pretty inefficient at subsonics speeds IIRC

I think the engines were designed to be most efficient at full speed, running pretty much as a ramjet.

Yep, but to get the engines running efficiently you need to get a shock wave on the cone, hence the dive from subsonic. Once the shock wave is there, the efficiency improves as you accelerate. There was an incident over Libya IIRC where a crew accelerated and climbed to avoid a SAM, and ended up beating their fuel curve (Although they probably cooked the turbine in the process......)

[Mave]

aeropilot said:

Talksteer said:

PugwasHDJ80 said:

I'm still stuck on the 4.5g frame limit.

at least the pilots won't need G-suits!

The g limts are 9g, 7g and 7.5g for the A, B and C models.

The 4.5g figure quoted is a sustained turn rate, which is a measure of drag at high angles of attack versus thrust. The F35 has a relatively small wing area and would be expected to bleed off speed quicker than an aircraft with a larger wing.

If that's the case, then why wouldn't the C version with it's bigger wing area have a higher sustained g limit than the A or B....?

Isn't it heavier?

[IanMorewood]

Mave said:

Yep, but to get the engines running efficiently you need to get a shock wave on the cone, hence the dive from subsonic. Once the shock wave is there, the efficiency improves as you accelerate. There was an incident over Libya IIRC where a crew accelerated and climbed to avoid a SAM, and ended up beating their fuel curve (Although they probably cooked the turbine in the process......)

Throttled back as soon as they left Libya and they still overshot the refueling tanker.

[LukeBird]

Mave said:

LukeBird said:

Talksteer said:

Interesting g stuff

All very well, but the two comparisons you have used are an F-4 and a very early F-16; the F-35 should be considerably beyond either of those for performance.

Why? The requirements were for legacy levels of A/A performance. It's not intended to be an air superiority fighter......

I appreciate the latter point, but surely and F-4 or early F-16 should be vastly inferior?
There's legacy and there's legacy...

[Mojocvh]

aeropilot said:

Talksteer said:

PugwasHDJ80 said:

I'm still stuck on the 4.5g frame limit.

at least the pilots won't need G-suits!

The g limts are 9g, 7g and 7.5g for the A, B and C models.

The 4.5g figure quoted is a sustained turn rate, which is a measure of drag at high angles of attack versus thrust. The F35 has a relatively small wing area and would be expected to bleed off speed quicker than an aircraft with a larger wing.

If that's the case, then why wouldn't the C version with it's bigger wing area have a higher sustained g limit than the A or B....?

Because of the mahoosivly increased drag of the mahoosivly larger wing compared to the other two pos.

[andymadmak]

Look! It's selling in biiiiiig numbers now.. The program is rescued.. the future is assured!

http://www.defenseworld.net/news/8226/Can_Foreign_...

Am I alone in thinking that boasting about selling 6 planes to Norway and less than 20 to Israel smacks a little of desperation?

[IanMorewood]

andymadmak said:

Look! It's selling in biiiiiig numbers now.. The program is rescued.. the future is assured!

http://www.defenseworld.net/news/8226/Can_Foreign_...

Am I alone in thinking that boasting about selling 6 planes to Norway and less than 20 to Israel smacks a little of desperation?

I don't think much of that is new news, most had already stated a firm interest in the F35 several years ago.

[hidetheelephants]

Sea Gripen: force multiplier for the indian navy

Florid SAAB salesblah said:

With a catapult launch Sea Gripen will be able to operate to its maximum takeoff weight of 16.5 tonnes, which will provide navies with Gripen EF performance and capability from a carrier base. Without catapult assistance, we are working on further methods to increase takeoff payload. Saab anticipates that Sea Gripen will offer a very capable payload performance from a 200 metre deck run, and 14 degree ramp exit.

The Sea Gripen is an ideal replacement for existing fleets, countries which will return to carrier based operations, and potential emerging aircraft carrier nations. Its footprint will allow it to operate from all existing carriers in service, and fit on every lift in operation worldwide.

Reading a manufacturer's spiel about vapourware is always a risky business, but it makes an interesting 'what if?'. If they actually gave a figure for a non-cat launch MTOW people might sit up and take notice.

[MartG]

I read somewhere that the latest E-2 Hawkeye could ( just ) make an unassisted takeoff from a skijump equipped carrier - but it required 100% power and any engine issue during the takeoff run would probably lead to the loss of the aircraft. While strapping a couple of JATOs to it would help, I don't think that would be very safe for anyone on the carrier's deck

[IanMorewood]

hidetheelephants said:

Reading a manufacturer's spiel about vapourware is always a risky business, but it makes an interesting 'what if?'. If they actually gave a figure for a non-cat launch MTOW people might sit up and take notice.

Indians will only buy it if they can have HAL build it themselves. That said they have a reasonable indigenous project going themselves.

[Mave]

Which project is that? I know India has some serious ambition to grow capability, any info on the fighter?

[RizzoTheRat]

India's involved in the Sukhoi PAK FA aren't they?

[IanMorewood]

Mave said:

Which project is that? I know India has some serious ambition to grow capability, any info on the fighter?

HAL Tejas