I have seen reports of up to 90mph but that seems high?
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1$\begingroup$ The F4U Corsair had a stall speed of 89mph, so landings were probably carried out well above 90. $\endgroup$– Ron BeyerCommented Mar 8, 2017 at 17:54
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$\begingroup$ Is it relative to the Carrier or air? $\endgroup$– LingCommented Mar 8, 2017 at 20:37
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$\begingroup$ @Ling stall speed always related to air. If you have a moving carrier you make it easier for the pilot. $\endgroup$– vasin1987Commented Mar 8, 2017 at 23:10
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2$\begingroup$ @vasin1987 Yes, but OP didn't ask about stall speed. Maybe he thinks 90mph is high relative to the carrier. $\endgroup$– LingCommented Mar 9, 2017 at 7:14
2 Answers
The stall speed of the F4U Corsair may be 89mph, and a safe approach speed might be 95-100mph, but that's airspeed... Measured with reference to the carrier deck, you have to substract 20mph headwind (nothing unusual at sea) and also around 30 mph of the carrier own speed. Hence, that plane touched down at a sedate 45-50 mph, with respect to the carrier deck...
It depends on the aircraft, but here's an example.
Consider the stall speed of the Grumman F6F Hellcat
Landing condition-power on - MPH 78.5
Landing condition-power off - MPH 86.0
According to this checklist, your abeam speed was 75 knots, once in landing configuration.
You'd want your approach speed to be above the stall threshold, which 75 knots is. Convert 75 knots to mph and you get 86 MPH. That's a tighter performance margin than typical approach speeds now which are typically 1.3 x stall speed. Each aircraft has its own performance margins. 90 MPH translates to about 78 knots which looks like a reasonable figure, depending on the type.
The F4U Corsair had similar performance.
Stall speed:
Landing condition - power on - MPH 74.5
The carrier will typically try to recover with about 25-30 knots of wind down the deck, which (by turning into the wind) will be a combination of the speed of the wind that day and the ship's speed. (We nautical types use knots, not MPH).
Subtract wind over the deck from the approach speed and you get "how fast over the deck" the aircraft is traveling as it touches down.
For a very similar configuration, here is a T-28C carrier approach and landing video. The T-28C is basically an updated WW II fighter/bomber used as a trainer. (I got my initial training in a T-28B. The C's were out of use by the time I got to flight school).
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$\begingroup$ Do you also know the speed of the carrier? It would of course be going at full speed to reduce the relative speed which matters for stopping. $\endgroup$ Commented Mar 8, 2017 at 22:22
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$\begingroup$ (WP says 32.5 knots maximum for Yorktown-class) $\endgroup$ Commented Mar 8, 2017 at 22:23
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1$\begingroup$ @Jan it's irrelevant in terms of the aircraft air speed, how fast the carrier is going won't change your stall speed, nor your approach speed. It will influence the relative motion and the final ground speed on touchdown (and thus runout, etc). $\endgroup$ Commented Mar 8, 2017 at 23:02
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1$\begingroup$ I didn't say it's relevant for air speed. It is not. But it is relevant for "ground" speed, and the question does not specify "air", so it might mean either. $\endgroup$ Commented Mar 9, 2017 at 7:46
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1$\begingroup$ @JanHudec I understand, your point, but the carrier doesn't travel at a fixed speed. What it tries to do is achieve a particular relative wind ... $\endgroup$ Commented Mar 9, 2017 at 13:07