how long can a jet fighter airframe last in heavy use?

>>63864246 (OP)
Depends on how often you replace things.
Technically indefinitely if you swap all the parts out over time for new parts.

>>63864313
The F15 of Theseus.

id imagine if the thing is frequently getting into high G maneuvers the amount of metal fatiguing hyper accelerates the wear. i wonder if this type of stuff is logged to the chassis.

>>63864380
does high G really mess with the frame? I thought that if the whole frame torques it's evenly distributed.

>>63865156
iirc past a certain G loading you must have technicians thoroughly check the airframe for stress/fagitue/problems more than the regular checks between flights. when pilots do that in peacetime they apologize to the ground crews for giving them extra work

>>63865166
that's so weird. i guess they have to prevent excessive wear and maintenance work, but i'd also want to have it tested to see it can still handle those Gs before exiting peacetime, but im sure they do that anyway. so the frame could in theory just rip itself apart under a high G maneuver if not taken care of huh.

>>63865175
The checks ensure that it can handle it, but you have to do them again if you put a significant amount of stress on the plane to ensure nothing is going to break next time you do it. There's little reason to do so during peacetime, but that doesn't mean that it's going to risk falling apart when stressed if needed.

>>63865175
20 tons doing 3g of acceleration is insane amounts of stress on certain parts yes

>>63864246 (OP)
Anywhere from one mission to the life expectancy of the aircraft. I'm sure somebody has fucked up an airframe in a high G maneuver and wobbled it back to base

>>63865196
>20 tons doing 3g
so that's why the viggen keeps blowing up on me in DCS world when i do high-g maneuvers...

>>63865201
yep

>>63864246 (OP)
>iran is losing to some crusty ass F-15s from the 80s
Dayum, how are they coping about it?

>>63865221
the kill mark is from
https://en.wikipedia.org/wiki/Operation_Mole_Cricket_19

>>63864380
It's logged to the airframe and to individual structural components. Once in a while major structural components (wing spars, ribs, the skin) are inspected for cracks and fatigue in general. Service life extensions involve taking it all apart and inspecting everything before the airframe gets cleared for more service life.
>>63865156
Simplifying things the wing is essentially a cantilevered beam, stress is not evenly distributed even in the evenly loaded case, and lift is not evenly distributed across the wing.

>>63865230
F-15I wasn't around back then

>>63865156
>does high G really mess with the frame?

lol. yes.

>I thought

Seriously, just stop. Leave it to others.

>>63865379
why do you type like a fag?

>>63865391
'cause my shit's all retarded.

Last week we saw a Su-25, which is pretty rugged, snap its wing off from a high-G maneuver. People were trying to sell it as a friendly fire, but a closer inspection revealed that the angles didn’t match: the plane simply failed from stress fatigue and broke. The reason why that doesn’t happen to the US all the time is because the US pays for extensive maintenance procedures — not to magically fix stressed frames, but to stop them from flying if when they’re found so as to not break in midair. If you baby the airframes, keep the engines refurbished and everything else maintained and with mid-life overhauls etc you can keep planes flying for many decades in fact.

>>63865156
my brother in christ do you have any idea how much stress that is on materials under those conditions? even with all the composite stuff you still have shit made out of aluminum