It's probably not too much of a conjecture to assume that these fit in front of the stator vanes and would be effectively supported by them, so would not come in contact with the the rotating turbine blades. Even if the turbine blades could create a vacuum, the maximum pressure it would have to hold is 14 pounds per square inch bridged between the vanes. I'd also guess that "cheap" is relative and they are using something between high-end commerical and engineering-grade plastic (still way cheap compared to the composites on the aircraft), and that this could withstand the pressures for at least the few seconds/minutes it took to fire it up and toss it in the drink.
I'm more surprised that they didn't notice it in firing up the engines - don't they run it briefly to full throttle as part of their checks? Seems it would at least sound badly off-tune, but what do I know...
None of it makes any sense at all.. there's no way one of those covers can stay on during engine startup without a million warning lights going crazy in the cockpit, there's no way the cover could possibly not get ingested during an engine runup.
And this was a carrier takeoff, so the engines would have been held at maximum thrust prior to launching off a catapult and possibly would have been run at afterburner as well. The inlet flow for that would develop far more than 14psi as the volume of air ingested is enormous. The mass of air ingested is measure in tons per second.
I think this is just incompetent journalists. Not that I've ever done pre-flight on an F-35 but there are probably MANY protective covers that have to be removed during preflight.
It most likely was another cover left on which did not impede takeoff but threw the systems for a loop after takeoff and the pilot wasn't well trained enough to figure out an emergency procedure on such short notice.
If it is actually a full inlet cover, there will be _zero_ airflow, so just < 14psi pressure on the cover. (I was just answering how it could avoid being ingested if it was a full cover.)
If it is some other smaller cover on some auxiliary inlet, it might make more sense, as it could definitely screw up the sensors, airflow, whatever, and not get ingested.
I'm sure we'll all be really interested to see what really happened, 'tho I'm not sure we ever will.
I doubt you'd be able to get up to full thrust with the covers on though. If it wouldn't be sucked in and shredded/burned (in which case it wouldn't be seen floating in the sea), it wouldn't be possible to get the amount of airflow you ned to get it up to full thrust for takeoff.
I agree this whole story is conjecture.. And a cover floating in the sea doesn't mean it would have had anything to do with this plane.
I'm more surprised that they didn't notice it in firing up the engines - don't they run it briefly to full throttle as part of their checks? Seems it would at least sound badly off-tune, but what do I know...
Major fck-up all around...