Ditching

[PantLoad]

Looking for a good source of information for ditching.

Any help?

[B737900er]

The aircrafts QRH and Flight crew training manual would be a good start.

[PantLoad]

Thanks.....Yes, I've done that.

Further question: 2182 KHz, as of 1 AUG 13, is no longer monitored by
the U.S. Coast Guard. However, is that frequency still monitored by the
rest of the world?

Anyone know?

[framer]

I'll keep this one rolling along.
Why do Boeing suggest landing parallel to the swells on the windward side of the swell when you would have a lower impact speed if you just flew directly into wind?

[oggers]

...I get the feeling you know but are just testing!

[Amadis of Gaul]

I have a sense this is fixing to deteriorate into a "why don't sharks eat lawyers" style debate.

Not that there's anything necessarily wrong with that...

[megan]

Why do Boeing suggest landing parallel to the swells on the windward side of the swellLanding into wind means touchdown is going to be somewhere between the crest and trough of the wave, and the height between the two can be considerable. Look at video of a ship and the degree to which it pitches when running into wind, trying to do the same at a touchdown speed of some 140 knots or so needs no imagination. Landing on the windward side means that you benefit from the updraft and the surface is going to be as level as you will find, and are removed from the downwind side of the crest which will be breaking if the wind is high enough. Since the wave set is moving it means that you will have a slight downwind component.

For a given wind the height of the wave is dependant upon the fetch. For a thirty knot wind the following fetch(nm)/wave height(ft) relationship applies

20/7.2
50/10.5
200/13.5

[PantLoad]

The U.S. AIM sheds some information on this.
(Airperson's Information Manual)

[Intruder]

Is there an Airperdaughter's Information Manual?

[PantLoad]

Yes, I know, it's stupid.

Now, it's the Aeronautical Information Manual.


Regardless, I'm having to do a presentation about ditching. Trying to
do the best job I can, I'm trying to consult every source of information
I can find. This is why I'm asking PPrue for help. You guys (persons)
are always good for discussions, information, etc.

As I research this topic, I've found that, effective 1 AUG 13, the U.S.
Coast Guard no longer monitors 2182 KHz. However, 2182 (I thought)
is an international HF emergency frequency. So, is 2182 KHz still valid,
and only the Coast Guard no longer monitors this frequency, or is 2182
no longer an emergency frequency worldwide? (i.e. No one monitors it,
anymore.)

I'm sure someone on PPrune knows the answer to this..... You guys
(people) are sharp.

[muncen]

Its a marine ship frequency , most modern aircraft's have the 406 frq nowadays, and its all satellite supported. If you insist on knowing why they terminated the 2182 at the coast guard, then a us coast guard might be helpful.

[Notthemainline]

http://http://publicapps.caa.co.uk/docs/33/20130121SSL21.pdf

[underfire]

Why do Boeing suggest landing parallel to the swells on the windward side of the swell when you would have a lower impact speed if you just flew directly into wind?

The last thing you want to do is to land head-on into a swell. Even with strong headwinds that slow down your landing speed, flying into a swell would be like running into a brick wall.

As a side note, who carries a seat belt knife.....http://www.equipped.org/graphics/zipknf1.gif

[DaveReidUK]

http://http://publicapps.caa.co.uk/docs/33/20130121SSL21.pdf

Bad link.

CAA SafetySense Leaflet 21d - Ditching (http://publicapps.caa.co.uk/docs/33/20130121SSL21.pdf)

[PantLoad]

Perfect!

This is exactly the type of thing I'm looking for!

Thank you, everyone!

[BGQ]

First off I need to establish that I have several thousand hours of water flying under my belt in aircraft that put the hull into the water (not a float plane).

It us all about support points and the length of the hull. Think about a 10ft piece of timber moving over a 12inch pipe. The forward end will easily rotate downwards into the ground. In an aircraft on a single wave as pitch control reduces the same can happen with the nose getting buried in the wave in front causing extreme stresses and possible destruction. Now think about the same piece of timber over 3 or more 12 inch pipes. Much more stability. Experienced sea plane pilots assess the size of the waves, the period between them and the size if their aircraft {length of the hull) along with the strength of the wind and make an intelligent decision whether to land into wind and across the waves or parallel to the swell.

Unfortunately most pilots ditching don't have the relevant experience so the guidance in the pamphlets and documentation provided by manufacturers and CAA authorities is written in generic form. In my opinion it should be followed. The two points I would add to most of them though are

Speed really counts... Water is hard when you hit it fast.. minimum speed should be used but not do not stall onto the water.

If you know you will have to ditch and you can do it with power (fuel running out or your aircraft is burning) ditch with power. You have a better chance of picking your touch down point, minimizing the speed and controlling the touch down

[Amadis of Gaul]

The last thing you want to do is to land head-on into a swell. Even with strong headwinds that slow down your landing speed, flying into a swell would be like running into a brick wall.

As a side note, who carries a seat belt knife.....http://www.equipped.org/graphics/zipknf1.gif
I used to carry a seat belt knife as well as a windshield hammer back in the days of my misspent youth in EMS.

[Brain Potter]

The NTSB report on the Hudson river ditching includes some interesting material about ditching techniques.

[noflynomore]

There is a post on the Private forum Tracey Curtis Taylor thread by Old Fat One which is all about his speciality of sea survival. (Within the last week). I'm sure you'll find it.

[A37575]

Next time you are in the simulator and the box ticking exercises are over ask the instructor if you can have a go at a simulated ditching - starting from 1000 ft and at night. Rate of descent no more than 200 fpm. VRef 40 (Boeing 737). All manual flying no autothrottle or FD.

Believe me it takes considerable instrument flying skill as you may not know exactly where the sea is. RA may not always be accurate in calm seas. Nor the barometric altitude depending on atmospheric pressure at your location. At no stage should you exceed 200 fpm and the nose attitude should be slightly nose high all the way down.

Guarantee you would go in like a dropped torpedo first time you try it in the simulator. Which is precisely why simulator practice is vital for this exercise.

[Canute]

Is the simulator valid for this exercise though? I suspect not since I very much doubt that trials were done to produce a data set.

[Mark 1]

This (http://www.equipped.com/ditchingmyths.htm) makes interesting reading.

[BGQ]

You are right.... No simulator can replicate the actual touchdown on the ocean largely because of the variable nature of the "runway" but you can develop a good approach technique using a simulator.



Is the simulator valid for this exercise though? I suspect not since I very much doubt that trials were done to produce a data set.

[mark.pilot]

Mark 1, thanks for this interesting link!
This article answers most of the open questions and hangartalk about ditching various airplanes.