aircraft minimum take off distance

[mikey]

I saw a picture o a p 47 taking off from a carrier I thought I read about the fighter taking all of the run way to get airborne

 

[Shortround6]

Depends on load and head wind.

http://www.zenoswarbirdvideos.com/Images/P-47/47TOCL.gif

With the weight going between 12,500lbs and 15,000lb and the head wind changing from 0 to 40mph the runway distance needed changes from 900 ft to 2400ft.

A number of those carrier take-offs (ferry operations) were done no ammo (in some cases limited guns) and limited fuel ( enough to reach the shore landing strip) to get the weight as far under 12,500 lbs as they could. And unlike a land take-off with a carrier take-off you can trade altitude (distance of flight deck above water) for airspeed. Works in calm waters when there is not a lot of time pressure to get the planes into the air.

 

[GregP]

It could take a long run whan heavily loaded, true. But if you were very light and had 30 knots over the bow into a 15 - 20 mph wind, you could do it as shown in the pics. That P-47 probably had something like 1/3 fuel and no ammunition or ordnance. It was probably a delivery flight, as stated in the original thread.

 

[tyrodtom]

That carrier isn't standing still, and if you look close at those pictures you'll notice they've got it hooked up to the catapult.

Both of those are going to reduce the takeoff distance quite a bit.

 

[GregP]

It's also possible the picture is a shot of a touch-and-go landing on the carrier, though I jave read somewhere they did catapult P-47's off carriers. Can't recall where ...

 

[GregP]

It's also possible the picture is a shot of a touch-and-go landing on the carrier, though I jave read somewhere they did catapult P-47's off carriers. Can't recall where ...

Seems like the catapults used on US WWII ships were rocket powered. Not too sure if steam-drien catapults ever saw use in WWII. Maybe a good thing to go looku up. I was under the impression the US started using steam-driven catapults on aircraft carriers in the late 1940's to 1950's timeframe, but that is just from memory.

 

[stona]

The US catapults or accelerators were hydraulic.

Here is a nice picture of a P-47 of the 78th FS, 318th FG being flung from the USS Manila Bay off Saipan on June 24th 1944.

The bridle (just detaching) was attached to an eye on the main landing gear. I don't know if it was saved or went over the bow as later ones did.

Cheers

Steve

 

[GregP]

Good shot!

Well, if catapulted, then perhaps they could have been armed a bit to fly a mission before delivery touchdown I'd have to go verify that before believing it, though.

The P-47 above has a belly tank on it, but you can't tell if has any fuel in it. Looks like bomb shackle under the starboard wing, but no bomb. Interestingly enough, he hasn't started to put in right rudder. I suppose the catapult has no touque to counteract until after you leave the end of the catapult.

 

[stona]

The aircraft above was on a ferry flight to Saipan. I can't remember the chronological order of the battle to overcome the Japanese there, but by this date the US forces must have controlled an airfield where the P-47 could land. It certainly couldn't land back on the carrier.
Since I don't know the maximum gross weight at which a P-47 could be launched in this way I can't comment on whether it would be carrying any ammunition. If someone does know that maximum weight it might be possible to make a guesstimate of how it was configured for the flight. It certainly wouldn't carry any more fuel than was needed for the one way trip.
Cheers
Steve

 

[vikingBerserker]

I read about this in the book The Little Giants , they aircraft were not fully fueled but did carry ammo. IIRC they only carried enough gas to land.

 

[gumbyk]

The P-47 above has a belly tank on it, but you can't tell if has any fuel in it. Looks like bomb shackle under the starboard wing, but no bomb. Interestingly enough, he hasn't started to put in right rudder. I suppose the catapult has no touque to counteract until after you leave the end of the catapult.

He's got full right rudder trim in, and it looks like the tailwheel is off the ground, so with full power on, he should have a bootful of right rudder. The catapult doesn't have any torque, but the engine sure does. Unless they were doing partial power take-offs.

 

[GregP]

I'd bet he had his feet placed firmly on the rudder pedals, was bracing himself for the cat shot with his feet together and legs locked, and wound up with a good deal of right rudder deflection almost immediately after this pic was snapped.

 

[gumbyk]

And he's about to go into a left turn, and probably not that current on ship-borne ops, would be interesting to see the same aircraft one second later...

 

[stona]

And he's about to go into a left turn, and probably not that current on ship-borne ops, would be interesting to see the same aircraft one second later...

Not the same aircraft, but from the same launch.

Plenty of rudder evident. The sun is coming over the bow as evidenced by the crewman's shadow, the deflection of the rudder is causing it to be lit quite differently from the fin.

Steve

 

[N4521U]

Looks like he has Just reached V1................

 

[gumbyk]

Not the same aircraft, but from the same launch.

Plenty of rudder evident. The sun is coming over the bow as evidenced by the crewman's shadow, the deflection of the rudder is causing it to be lit quite differently from the fin.

Steve

Thinking about it more, if the tailwheel was locked, he wouldn't need as much rudder input with the tail on the ground.

On a cat launch, V1 would be about 1 knot...

 

[BiffF15]

Gumbyk,

I actually think V1 would be an action and not a speed in this case (the pulling of the launch trigger). Once done you are going regardless of speed.

Cheers,
Biff

 

[stona]

Gumbyk,

Once done you are going regardless of speed.

Cheers,
Biff

Me too. That's almost exactly what my father said, flying the Sea Fury from RN carriers. You were going to fly, or going into the sea. He said the same about RATOs

Steve

 

[gumbyk]

That's what I meant. 1 knot... would be showing on the airspeed indicator before triggering the cat.

 

[GregP]

The airspeed indicator would be reading the relative wind across the bow of the carrier. Hopefully whatever breeze they sail into plus some 30 knots ship speed or however fast they launched.