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I'm trying to determine the pre-impact pitch of a two blade McCauley variable pitch on a Cessna 210 that hit shallow ocean water (8 feet, mostly sand) shortly after takeoff from an altitude of 300 feet at 140mph at a shallow angle of attack. I also have picture of the prop pitch knob, which seems to be pulled out for landing rather than pushed in for takeoff. I want to know if the pilot failed to gain altitude because the prop was never set for takeoff and it would leave a mark on the blade when it hit, showing what angle the blade was at. Any ideas based on the photos?

Image of the McCauley variable pitch propeller (post impact)

Image of the throttle/pitch/mixture control levers

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    $\begingroup$ look up Ross R. Allen on Linkedin. He has dealt with the question of prop pitch effect on impact marks in airplane crashes in his consulting business. -NN $\endgroup$ Mar 6, 2023 at 3:13
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    $\begingroup$ Any reason to believe that the FAA/NTSB won't be looking at this? $\endgroup$
    – RetiredATC
    Mar 6, 2023 at 4:00
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    $\begingroup$ I'd consider looking for witness marks inside the hub due to other variable affecting how the blade bent. But then the investigators would be trained in this. $\endgroup$ Mar 7, 2023 at 0:45
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    $\begingroup$ The accident was already investigated and a report made by NTSB years ago. Pilot spatial disorientation and vestibular illusion. The plane was scrapped and I was able to obtain some of the parts as well as take pictures of the plane while it was at the plane graveyard. My ex was aboard that plane. NTSB did not mention the position of the pitch knob or the pitch of propellor at impact. Also, the altimeter read 2,400 feet but the only ascended to barely 400 feet. Pilot was instrument rated and experienced; but if his static port was blocked and his pitch mechanism was shot he had no chance. $\endgroup$
    – Argonaut5
    Mar 7, 2023 at 5:02
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    $\begingroup$ @Argonaut5 I'm so sorry for your loss. I hope whatever comes if this it will bring you peace. God bless you. $\endgroup$
    – RetiredATC
    Mar 8, 2023 at 22:00

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I'm sorry for your loss.

It's probably impossible to determine the pitch of the propeller at the time of impact just from the propeller damage. You may be able to confirm or reject your hypothesis based on the recorded performance of the aircraft, however.

From your description, this sounds like it's probably referring to NTSB accident number ERA19FA266. The ADS-B track in that report indicates that the plane reached its peak altitude (which the final report says was 425 feet indicated) around 20 seconds after takeoff, while the final report indicates that it accelerated from 70 knots at liftoff to about 100 knots at its highest point. (As an aside, the existence of ADS-B data indicates that the altimeter was operative at the time of the crash).

In other words, it was able to maintain an average climb rate of around 1200 fpm while in a bank and simultaneously accelerating 30 knots in 20 seconds. A Cessna 210B manual I found online indicates that the expected rate of climb at vy is between 1270 and 1900 fpm, so this doesn't sound like an airplane struggling to climb.

It's a sad fact that many fatal cases of spatial disorientation involve a pilot who is instrument rated and current. The pilot departed VFR (as they had not called ATC to pick up a clearance) and may have been depending on visual references. The sudden loss of visual references as he turned over a dark ocean on a cloudy early morning may have caused spatial disorientation that was simply too much to overcome.

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  • $\begingroup$ Thank you so much Chris for your response and observations. Your comment on the altimeter was very helpful. I took a picture of the post accident altimeter and the dials read about 2,400 feet so I had thought the dials were stuck from a blocked static port at that altitude prior to the crash. The passenger had turned her iphone flashlight on a few seconds before impact, so perhaps he had trouble seeing the instruments. I also accept your assessment of the climb rate. It's still hard for me to grasp why he left so early when 15 minutes later the visibility was so much better. Thanks so much! $\endgroup$
    – Argonaut5
    Jul 19, 2023 at 7:02

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