Lockheed Martin F-35 Lightning II Joint Strike Fighter (JSF)

1680190587205
 
rooster said:
Moose said:
https://www.thedrive.com/the-war-zo...o-hot-due-to-under-speccing-upgrade-now-vital
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Wonder if the engines will now be rated for fewer thermal cycles
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The F-135 actual mission usage is downloaded into the ALIS system after each flight and run through a structural thermal model that calculates life usage on each tracked component for that flight. It is no longer just hours or the number of cycles through rotor speed gates. However, running a higher average Turbine Inlet Temperature will debit the life of the hot section parts quicker than originally expected when the engine usage was specified in the contract.
 
F119Doctor said:
TomcatViP said:
My dear @F119Doctor, I fear @sferrin comment was ironical, following the cancelation of the AETP upgrade ;)
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and I thought he was referring to the F135 ECU path chosen by the F-35 Program Office….

But my response was specifically to Moose’s question regarding reduced thermal cycles
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Either works I suppose. I'd have preferred they went with the AETP engine but they wouldn't have been able to use it on the B anyway. I'm surprised the USN didn't want it on the F-35C but then I get the impression the USN still doesn't know what stealth is for so. . .
 
Manuducati said:
F-35B weapons bays are smaller (and can't carry as much weight) mainly because of the lift fan.
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How does the lift fan affect the size of the bays?

The lift fan is on the centerline and clearly in front of the two laterally arranged IWBs. I also don't see that the lift fan doors at the bottom have an impact and couldn't find any picture that support this theory.
 

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VTOLicious said:
Manuducati said:
F-35B weapons bays are smaller (and can't carry as much weight) mainly because of the lift fan.
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How does the lift fan affect the size of the bays?

The lift fan is on the centerline and clearly in front of the two laterally arranged IWBs. I also don't see that the lift fan doors at the bottom have an impact and couldn't find any picture that support this theory.
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The LiftSystem also has gearing that runs through to the engine. F-35B internally will only take up to 1,000lb JDAM. No 2,000lb munition will fit, unlike the A and C variants. Internal carriage of weapons like JSM is also not possible.
 
VTOLicious said:
Manuducati said:
F-35B weapons bays are smaller (and can't carry as much weight) mainly because of the lift fan.
Click to expand...

How does the lift fan affect the size of the bays?

The lift fan is on the centerline and clearly in front of the two laterally arranged IWBs. I also don't see that the lift fan doors at the bottom have an impact and couldn't find any picture that support this theory.
Click to expand...

It doesn't, not directly anyway. The Marines only required internal carriage of 1,000 lb munitions, while the other services required larger munitions. Originally LM intended all three variants to use a common weapon bay capable of holding 2,500 lb weapons. That plan however was ruined by rapid weight growth in 2003-04. Weight growth was particularly bad on the B model, which unlike the others had a hard physical limit due to the requirement for vertical flight. This required a major effort (called SWAT) across the program to remedy with design changes to all variants, ultimately reducing parts commonality and certain capabilities, the most visible being reducing the B variant's weapons bay back to the original USMC requirement. This was accomplished by shortening the aft end of the bays, the front portion of the bays is in pretty much the same spot as on the other variants.
 
https://aviationweek.com/defense-sp...ll-f135-upgrade-only-option-all-f-35-variants
Wholehearteadly agree with him on this! I know i'll probably get some flak, but in a way i'm happy that cool heads prevailed and decided not to go with the uber-expensive AETP reengine route. With the current budget realities, it was a matter of time before being forced to choose which aircaft do you want new engines to go in: F-35, or NGAD. And siding with the F-35 would have meant no NGAP. Aka: A repeat of the YF-119 vs YF-120 saga, except this time propitiated by lack of cash.
For starters, besides the integration troubles with the B and C variants, is it worth the hassle when it's combat range isn't that great to begin with ?(for the Pacific) Yes, the XA-100 would have provided a 30% increase, but how much is that?

Hastily made comparison of what a 30% increase would look like without taking other factors into account.
F-35A​
F-35B/STOVL​
F-35C​
669nmi, 6.69*30+669=869nmi505nmi, 5.05*30+505=656.5nmi670nmi: 6.7*30+670=871nmi

I mean it's good, but not that much of an improvement, measly 200nmi, with only 150 for the B. The MQ-25, set to enter service in 2026, and adding couple of LO EFT's under each wing could extend it to 1400-1700nmi and i feel still wouldn't be enough for the distances of the Pacific and/or to safely operate outside the Chinese A2/AD bubble. For an engine upgrade to be effective, an obligatory combat radius of at least 1000nmi on internal fuel would be ideal.

Now let's see how a mix of historical, current and proposed planes would fare with ACEs , again a very simplistic calculation, without payload, altitude, speed or weight considered.

CAC J-20​
Convair B-58​
GD F-11B​
LM FB-22(Concept)​
Combat radius: 1100nmi 11.0*38+1100=1518nmi
Combat radius: 1740nmi
17.4*38+1740=2401.2nmi
Combat radius: 1830nmi
18.3*38+1830=2525.4nmi
Combat radius: 1800nmi
18*38+1800=2484nmi

30% vs 38% increase in radius! That's insane! NGAD is supposed to be BIG, so how far it could go, compared to all F-35 versions, would increase exponentially the more fuel the plane carries. It is obvious the bearing costs of a retrofit wouldn't have been worthy, and a larger plane with deeper fuel tanks capable of crossing vast distances from the start will see itself more beneffited than a small airframe.

(Meanwhile, in an AU, those in charge are pulling their hairs after the NGAP effort stalls in favor of developing a conventional turbofan engine, resulting in a 6th gen with Ok-ish reach and watered down capabilities, since the funds that otherwise would've been allocated to its development were eaten giving F-35s new shiny engines! Buy hey, that's what mattered, right?)

(Everything written above is entirely subjective and just my 2 Cents opinion)
 

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Sweet geez... 72 fighters a year... that's 2/3rd of the entire French AF Rafale inventory, build painstakingly since... 2004.
 

Just in time’ F-35 supply chain​

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"Just in time" is the worst idiocy ever happened to logistics in the last half-century. Toyota, how we hate you.

One day some asshole awoke and said "stocks are too expensive ! Let's cut them to the bone to save precious storage area". So no more stock, or very few spares. If you need it, just procures / buys it on the spot - because no more stock.

I've been working in logistics since 2015 and I saw the level of absurdness triggered by that concept.

Such as one low cost airline stretched across Europe if not north africa, with a fast growing fleet of Airbus, yet only two spares at... someplace in Europe.

Bottom line: if that peculiar aircraft part breaks and the FAA or EASA grounds the plane, the whole company across Europe erupts in mayhem and chaos just to get the one or two spare... someplace, to the aircraft (and angry passengers) stranded... someplace else, usually half a continent away.

We saw the logical end of that idiocy during the COVID crisis with the masks...
 
I think the problems lies also that people like key words. Aside of Rolex, Gucci or BMW, some professionals like to have them embedded in their work attires. Hence using tools that aren't relevant to actual needs.

Certainly, you are absolutely right, Maintenance isn't something that should comply with lean manufacturing.
 
X-39 said:
https://aviationweek.com/defense-sp...ll-f135-upgrade-only-option-all-f-35-variants
Wholehearteadly agree with him on this! I know i'll probably get some flak, but in a way i'm happy that cool heads prevailed and decided not to go with the uber-expensive AETP reengine route. With the current budget realities, it was a matter of time before being forced to choose which aircaft do you want new engines to go in: F-35, or NGAD. And siding with the F-35 would have meant no NGAP. Aka: A repeat of the YF-119 vs YF-120 saga, except this time propitiated by lack of cash.
For starters, besides the integration troubles with the B and C variants, is it worth the hassle when it's combat range isn't that great to begin with ?(for the Pacific) Yes, the XA-100 would have provided a 30% increase, but how much is that?

Hastily made comparison of what a 30% increase would look like without taking other factors into account.
F-35A​
F-35B/STOVL​
F-35C​
669nmi, 6.69*30+669=869nmi505nmi, 5.05*30+505=656.5nmi670nmi: 6.7*30+670=871nmi

I mean it's good, but not that much of an improvement, measly 200nmi, with only 150 for the B. The MQ-25, set to enter service in 2026, and adding couple of LO EFT's under each wing could extend it to 1400-1700nmi and i feel still wouldn't be enough for the distances of the Pacific and/or to safely operate outside the Chinese A2/AD bubble. For an engine upgrade to be effective, an obligatory combat radius of at least 1000nmi on internal fuel would be ideal.

Now let's see how a mix of historical, current and proposed planes would fare with ACEs , again a very simplistic calculation, without payload, altitude, speed or weight considered.

CAC J-20​
Convair B-58​
GD F-11B​
LM FB-22(Concept)​
Combat radius: 1100nmi 11.0*38+1100=1518nmi
Combat radius: 1740nmi
17.4*38+1740=2401.2nmi
Combat radius: 1830nmi
18.3*38+1830=2525.4nmi
Combat radius: 1800nmi
18*38+1800=2484nmi

30% vs 38% increase in radius! That's insane! NGAD is supposed to be BIG, so how far it could go, compared to all F-35 versions, would increase exponentially the more fuel the plane carries. It is obvious the bearing costs of a retrofit wouldn't have been worthy, and a larger plane with deeper fuel tanks capable of crossing vast distances from the start will see itself more beneffited than a small airframe.

(Meanwhile, in an AU, those in charge are pulling their hairs after the NGAP effort stalls in favor of developing a conventional turbofan engine, resulting in a 6th gen with Ok-ish reach and watered down capabilities, since the funds that otherwise would've been allocated to its development were eaten giving F-35s new shiny engines! Buy hey, that's what mattered, right?)

(Everything written above is entirely subjective and just my 2 Cents opinion)
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I think going with F-35 ECU is good from the cost stand point but I think it is terrible from the performance stand point
1- How many NGAD will they make ? consider that it is much bigger than F-22, I think it will be extremely expensive and surely can't have the same quantity as F-35
2- As the back bone fighter of USAF and USN, F-35 kinematic is really bad compared to other 5 gen aircraft. F-35 has terrible T/W compared to Su-57 and J-20.
At 50% fuel and 6 AAM
F-35A with F-135 => T/W = 1.05
F-35A with F-135ECU => T/W = 1.17
Su-57 with AL-41F1 => T/W = 1.24
Su-57 with izdeliye 30 => T/W = 1.45
J-20 with WS-10B => T/W = 1.11
J-20 with WS-15 => T/W = 1.54
Even worse if we recall that J-20 and Su-57 can fly further on 50% fuel
 

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