Water ditching technique

[Vliegskaap]

Background:
Most of my flying is of the around-the-patch variety. My home airfield is Wingfield in the Loch Vaal area of the vaal river and the threshold of the downhill runway that is mostly used for take-off is the river. In case of EFATO you have very limited options if under probably 400ft so a ditching is the most likely outcome. Also flying is mostly along the river. Admittedly there are options along the river where a forced lob can be done, but for the purposes of this question lets assume that a water ditching is what is going to happen.

Scenario:
Engine failure just after take off or whilst cruising along the river, with NO options of landing on land.

Assumptions:
Plane is a J3 cub. So everything happens at pretty much 60mph. At typical height cruising along river, one could probably get it up to 80mph.
Only pilot, no passenger.
Water is calm and smooth.
Low time pilot.

Question:
In the ditching process, do you descend to just above river and hold off to do a stall landing (3pointer at about 35mph) and plonk into the river?
Or do you descend and try to build up speed (80mph) and try to 'land' the plane in a wheeler attitude to get the main wheels on the water (similar to that famous photo of the Harvards doing it in formation on the Hartbeespoort dam) and let the water slow you down to very low (?) speed before aircraft sinks. (Higher speed allows the surface tension of water to keep you on top of water whilst speed is high enough.)

I have my ideas on each of these options but would appreciate some input from the old hands. I guess the outcome I am looking for is for the plane to not flip over so that one can be as oriented as possible when exiting plane whilst water is rushing in.

[Ray W]

I would say that without any power available I'd go for the three point attitude and as close to stall speed as possible. In my opinion this would cushion the landing considerably. Anybody who has ever fallen off water skis will know just how hard the water actually is. I would not go for the wheeler attitude because there is a good chance of her flipping over as the wheels dig in.

[gear up]

I'd say be careful of depth perception over water and agree with Ray, try and touch down as slow as possible but this will be a interesting topic nonetheless...

[Fransw]

Yes , very interesting topic! ...WATERLANDINGS.

I once saw a video of a RV7a doing a waterlanding in front of a crowd on a beach. The water was maybe a foot or 2 deep there. The moment it hit the water the plane flipped, lucky for the pilot the crowd came to the rescue and turn the plane around..

Rudi Greyling placed the video on avcom a while back, I can't find it!....

[Walter105]

Yes , very interesting topic! ...WATERLANDINGS.

I once saw a video of a RV7a doing a waterlanding in front of a crowd on a beach. The water was maybe a foot or 2 deep there. The moment it hit the water the plane flipped, lucky for the pilot the crowd came to the rescue and turn the plane around..

Rudi Greyling placed the video on avcom a while back, I can't find it!....

That RV was involved in a mid air collision that necessitated the water landing IINM.

I reckon three pointer is the way to go...the less energy you carry into the water landing the better the chances of staying upright being able to walk (swim) away from it...

[GeraldNagel]

.

[Fransw]

Yes , very interesting topic! ...WATERLANDINGS.

I once saw a video of a RV7a doing a waterlanding in front of a crowd on a beach. The water was maybe a foot or 2 deep there. The moment it hit the water the plane flipped, lucky for the pilot the crowd came to the rescue and turn the plane around..

Rudi Greyling placed the video on avcom a while back, I can't find it!....

That RV was involved in a mid air collision that necessitated the water landing IINM.

I reckon three pointer is the way to go...the less energy you carry into the water landing the better the chances of staying upright being able to walk (swim) away from it...

Walter, I don't think its the same RV. The 'crowd' was normal beach bathers. Engine was out, it would have been a perfect beach landing, but the pilot had no option to choose the shallow water to avoid the people.

It came in slow and smooth..perfect, but the moment the wheels touched the water the plane flipped and some guys help to turn it over. Lucky pilot!

Think it was in Spain somewhere. But anyhow that was an eye opener for me on waterlandings.

[RudiGreyling]

Would not recommend water landing, 2 tumble videos here

http://avcom.co.za/phpBB3/viewtopic.php?f=64&t=157390

[Vliegskaap]

Would not recommend water landing, 2 tumble videos here

http://avcom.co.za/phpBB3/viewtopic.php?f=64&t=157390

Hi Rudi

Agreed, not ideal. But the assumption is that you are in a situation where you HAVE to ditch. The question is what is the best approach.

The things that made me wonder if high speed wheeler type landing where you use water to slow you down in controlled fashion is possible, was:
1. As stated in initial post, the trick where harvards flew 'on top of water' at high speed. The speed creating enough surface tension in water to support planes to an extent. https://youtu.be/01E_6oxvlQA

2. The numerous videos you see of backcountry pilots landing on sand bars but sticking the wheels on the water 5 or more meters before the shore. Like this
https://youtu.be/21El16OPZoc

Admittedly in both above examples you have power and large wheels to help your cause, but it still made me wonder about this. My concern with coming in slow, in 3 point attitute and stalling it in, is that you will be plonking down in the water at slow (but still probably 30+mph) speed with a highish vertical component and that the wheels will then definitely push through the water and bite, possibly causing a nose over.

If it could be possible to wheel it on at higher speed and in ideal circumstances, it could be like a water skier that lets go of the rope and then slows down until speed is almost zero and then just sinks. (I do concede that high speed and J3 cub should probably not be used in 1 sentence)

Trying to learn here and be sure of what my plan will be in a situation like this. Don't want to be considering the physics and merits of each example as I am setting up the approach for ditching!

[rare bird]

Would not recommend water landing, 2 tumble videos here

http://avcom.co.za/phpBB3/viewtopic.php?f=64&t=157390

agree with Rudi
avoid water at all costs.
it just complicates everything 10 x
(I have also observed that many of our local ambulance & firemen are not able to swim) have observed this with vehicles that ended up in the brink - everyone just stands around at the edge of the water and looks on, waiting for eg the police divers, by which stage the people have al lankal verdrink.
having done the helicopter survival dunking course myself, I can tell you it is very disorientating to be upsidedown under water (and possibly with a bump on the head!) and trying to disentangle oneself to egress.
don't do it! rather get on land even if the options don't look good!

[rare bird]

talk to Scully (or anyone in the team) to find out about their pre-planning & testing that was done before the water-skiing effort - this was not just a spur of the moment thing! they had divers, medics etc standing by, just in case! Scully got the idea from the Canadian & Alaskan guys, but remember that their density altitude is much better than ours! Sitting at your DA at Vaal dam your performance is not as good for a STOL landing on a sandbank - you will take much more space than someone in Alaska! (whether you use the water as a clearway or not).
Water is bad news, klaar.

[Fransw]

..a bit of the topic, but i think a ballistic rescue shoot is a must have for long water crossing! Waterlandings are just to risky.

[Fransw]

..a bit of the topic, but i think a ballistic rescue shoot is a must have for long water crossing! Waterlandings are just to risky.

Its a ballistic chute no 'shoot'

[heisan]

Question:
In the ditching process, do you descend to just above river and hold off to do a stall landing (3pointer at about 35mph) and plonk into the river?
Or do you descend and try to build up speed (80mph) and try to 'land' the plane in a wheeler attitude to get the main wheels on the water (similar to that famous photo of the Harvards doing it in formation on the Hartbeespoort dam) and let the water slow you down to very low (?) speed before aircraft sinks. (Higher speed allows the surface tension of water to keep you on top of water whilst speed is high enough.)

I have my ideas on each of these options but would appreciate some input from the old hands. I guess the outcome I am looking for is for the plane to not flip over so that one can be as oriented as possible when exiting plane whilst water is rushing in.

Never try the wheeler. The moment your speed bleeds off, the wheels will sink in, and you will go over. And you will still have a hell of a lot of energy to bleed off.

Flare to a full stall, with the tail kissing the water will be your best bet.

[rare bird]

water ditching seldom has a good outcome. Sully Sullenberger on the Hudson was an exception - attached picture shows the damage to the aircraft!
I still get the impression someone wants to try water-skiing. there are a couple of folks who have ended up second best! not worth it. even the water-skiing Harvard team said they would never do that in their own aircraft!