Ditching B737 - QRH advice missing speed additives?

[Tee Emm]

From the Boeing 737 QRH>

Ditching Final
LANDING GEAR lever. . . . . . . . . . . . . . UP and OFF
Flaps . . . . . . . . . . . . . . . . . . . . . ___, Green light
At 500 feet, advise the cabin crew that ditching is
imminent.
At 50 feet, advise the cabin crew to brace for
impact.
Maintain airspeed at VREF. Flare the airplane to
achieve the minimum rate of descent at touchdown.
Maintain 200-300 fpm rate of descent until the start
of the flare.
At flare, rotate smoothly to a touchdown attitude of
10-12°. Maintain airspeed and rate of descent with
thrust.
At touchdown, reduce thrust to idle.

............................................................ ..........

Note there is no mention of speed additives to account for headwind component or gust factor. If these additives are required for landing on dry land - why not on water?

[bingofuel]

to account for headwind component or gust factor

Who is going to give you this information in the middle of the ocean?

[jidder]

Perhaps because it's a power on landing and there is no limitation on the landing distance?

Though I'm sure once connected with the water the landing roll/cartwheel will be alot shorter than on dry land:}

Just a guess...

J:E

[Avenger]

you are ditching parallel to waves, there should be no wind corrections, just maintain Vref. Frankly, unless you ditch on a mill pond the chances are slim, more speed just means the A/C breaks up or cartwheels more rapidly

[Yobbo]

Ditching parallel to the waves is never mentioned in any of the QRH,s of any manufacturer I have flown . Seems to me a much more important consideration than VREF additions. If I remember correctly years ago Lufthansa suggested ditching with the gear down and full flaps, the idea being they would help with the initial impact.

[D O Guerrero]

If the gear is the first thing to hit the water, wouldn't that result in an extremely rapid deceleration resulting in the nose smacking into the water? The idea, as I understand it, is to get the tail into the water first, to avoid having other dangly bits like engines causing the thing to immediately flip over. Slim chance of things working out - but it has been done.

[Denti]

@Yobbo, step 4 of the 737 ditching checklist states:

4 Plan to touch down on the windward side and parallel to waves and swells.

And yup, it is a bad idea to have the gear out for a ditching. And even engines are not good to touch first, therefore the unusually high touch down pitch of 10 to 12°.

[EW73]

Guys...

From my many years of flying P3s mid ocean, let me suggest to you...

1/ If possible, determine the swell direction from above 2,000 feet.
The direction of the swell will be the overriding factor in the heading you take up for the ditching.

2/ Offset this heading (parallel to the swell ) slightly as required for the effect of surface wind direction.

The swell can be much, much higher/bigger than any waves, and is mostly very difficult to pick out at low altitudes.

Flying into wind and meeting a sizable swell at the wrong angle is roughly the same as flying into a brick wall!

Also, don't forget to not open the rear pax doors after the ditch, as they may be partly submerged.

Cheers
EW73 :)

[Tee Emm]

From my many years of flying P3s mid ocean, let me suggest to you...

1/ If possible, determine the swell direction from above 2,000 feet.
The direction of the swell will be the overriding factor in the heading you take up for the ditching.

In another era we flew Daks (DC3) on night freight runs Melbourne to Tasmania. For those unfamiliar with the area it meant flying across the Tasman Sea known for its rough weather. Flight planning included obtaining the direction of surface winds and of the primary swell. The idea was to have a planned ditching heading already in your mind in case the impossible happened and a ditching was necessary. Chances were the ditching would be IMC so no hope of observing the waves at the last second when they would be illuminated in the landing lights (if electrical power still available)

This meteorlogical facility is probably still available although I doubt if pilots use it nowadays.