Sixteen bombers off a carrier deck: the Doolittle Raid's 467-foot gamble

[TheIronDiaries]

April 18, 1942. Sixteen B-25 bombers had to get off the deck of the USS Hornet in 467 feet, in heavy seas, 650 nautical miles from Japan, ten hours earlier than planned because a picket boat had spotted the task force.

I put together a short documentary on the raid and what it cost. Every one of the sixteen planes was lost, fifteen crews came down over China, one was interned at Vladivostok, and 69 of the 80 men eventually made it home. Roosevelt would only say the planes had launched from Shangri-La.

Video here:
View: https://www.youtube.com/watch?v=3yPAlVqkhN8

The part I keep coming back to is the morning routine on that deck, not the bombing itself. Getting sixteen bombers airborne in under an hour, in those seas, was the raid before the raid. Happy to be corrected on any detail. Sources are in the description.

 

[Alan Stevens]

The takeoff length was heavily practiced on land.
From a 32 knot flight deck into the wind helped.

 

[EwenS]

The takeoff length was heavily practiced on land.
From a 32 knot flight deck into the wind helped.

Oh dear the old myth of carriers needing to run around at over 30 knots during launch sequences!

The wind on the morning of 18th April 1942 was recorded at 20 knots and gusting. There was rain and heavy seas that occasionally landed on the flight deck.

See DANFS. Hornet is recorded as having worked up from her cruising speed to 15 knots at 0803, then to 20 knots at 0810 and 22 knots at 0814 which she maintained during the launch sequence.. At 0821 she began launching the B-25s. So about 42 knots wind over the deck. Trying to drive the ship faster in those conditions would probably have resulted in damage to her forward flight deck, shortening the deck length and possibly even leading to the raid being aborted. Photos of Hornet that morning pitching in those heavy seas.

https://www.navsource.net/archives/02/020806b.jpg

https://www.navsource.net/archives/02/020807.jpg

The secret to successfully launch any aircraft from a carrier in heavy seas even today is timing. The aircraft needs to arrive at the end of the flight deck as the ship pitches upwards as it rides to the crest of the wave, and not downwards as it heads for the trough.

If you want to see the effects of heavy seas on US carrier flight decks you just need to look at what happened to CV-12 Hornet in the June 1945 typhoon.

https://www.navsource.net/archives/02/021203.jpg

CV-20 Bennington again in June 1945.

https://www.navsource.net/archives/02/022025.jpg

Postwar the USN adopted enclosed "hurricane" bows with the SCB-125 Essex conversions for just this reason.

If you look at the photos taken on board during the transit across the Pacific, it is clear the deck crews got plenty of practice moving the heavy B-25s around the flight deck as they respotted the deck.