military fatigue assessment & washout

[nzhills]

Hi,

1. How does the military go about estimating the fatigue life / usage of their machines, be they aircraft or choppers? Is there a US military procedure where you put in the weight carried, flight path loading, (i.e. is it just a standard 1.1g - 1.2g flight or did it have a hard landing) / environment, (was the flight low down in rough air)? Then from this you can work out how much airframe life was used? I imagine for the choppers the engines and transmissions would have hard times/lives, but would how would the airframe usage be accounted for? Would the modern military choppers, i.e. NH90, be any different?

2. Does anyone know the washout applied to the wing of the F/A-18A and was it changed as this airframe progressed through to the E/A-18G?

Regards
Mark

[NutLoose]

Fighters have g meters from which fatigue is calculated. you are really in the wrong section, it would be better asking in the military pilot section.

https://www.seonics.co.in/fatigue-meter.html

this may help you

https://www.vttresearch.com/sites/default/files/julkaisut/muut/2013/ICAF_FinlandReview_2013_issue1_3April13.pdf

[PDR1]

Actually most military aircraft after about 1990 have fatigue-monitoring computers as a standard avionic fitment. The algorithms used come from the Main Airframe Fatigue Test or equivilent (a rig test done by the aircraft manufacturer, not the military) and are updated as the MAFT progresses. A good FMC monitors data from various sources including stress instrumentation built into the airframe and calculate life consumption in real time.

PDR