skipness1E
Topic Author
Posts: 4191
Joined: Sun Aug 19, 2007 9:18 am

Ditching a high wing aircraft-would it roll inverted?

Mon Oct 15, 2018 2:27 pm

Sully showed that ditching a low wing airliner is possible safely. However if my day went wrong and the ATR or Dash 8 I was on was forced to ditch, would it float on the wings with the cabin submerged and me drowned or roll inverted with the weight of the engines?
 
User avatar
TWA302
Posts: 416
Joined: Mon Jul 04, 2005 12:17 am

Re: Ditching a high wing aircraft-would it roll inverted?

Mon Oct 15, 2018 2:43 pm

Probably one of the most awkward questions I have seen posted here, but I guess the answer to your question is here?? I say that with a question mark too.
https://en.wikipedia.org/wiki/Tuninter_Flight_1153
 
mxaxai
Posts: 651
Joined: Sat Jun 18, 2016 7:29 am

Re: Ditching a high wing aircraft-would it roll inverted?

Mon Oct 15, 2018 3:05 pm

TWA302 wrote:
Probably one of the most awkward questions I have seen posted here, but I guess the answer to your question is here?? I say that with a question mark too.
https://en.wikipedia.org/wiki/Tuninter_Flight_1153

Very interesting. Never heard of that crash until now.

Among many other excellent points regarding ditching an aircraft, this article discusses the pros and cons of high vs low wing aircraft:
Another subject of controversy is the relative seaworthiness of high-wing versus low-wing airplanes and fixed gear versus retractable gear. Most pilots contend that the ideal airplane for ditching is a low-wing aircraft with landing gear retracted. Statistics, however, do not substantiate this. Aircraft geometry and landing gear configuration do not appear to affect survivability appreciably.

Although low-wing aircraft do offer superior planing and buoyancy (especially with empty fuel tanks), they should not be landed in water with flaps fully extended because this can cause pronounced nose-down pitching and make the aircraft behave like a submarine. Also, flaps hanging from a tow wing may be torn away during touchdown, which might create gaping holes in the wings and have a disastrous effect on buoyancy. Consequently, low-wing airplanes typically land faster, increasing the probability of damage and injury.

Since the flaps of high-wing aircraft are less susceptible to water damage, they should be used to the maximum extent possible to reduce impact speed.

http://www.equipped.com/bschiff-ditching.htm
Among the other points, this one surprised me most:
Whether an aircraft sinks or floats does not appear to effect the excellent survival rate. [...] Although less than 15% of all ditchings involve fatalities, the U.S. Coast Guard points out that most of those who perish usually survive the procedure itself.
 
User avatar
Erebus
Posts: 682
Joined: Tue Oct 20, 2015 2:40 am

Re: Ditching a high wing aircraft-would it roll inverted?

Mon Oct 15, 2018 5:45 pm

What is a typical approach speed for a turboprop like the ATR or Dash 8?
 
Okie
Posts: 3893
Joined: Wed Jul 16, 2003 11:30 am

Re: Ditching a high wing aircraft-would it roll inverted?

Mon Oct 15, 2018 10:42 pm

skipness1E wrote:
Sully showed that ditching a low wing airliner is possible safely. However if my day went wrong and the ATR or Dash 8 I was on was forced to ditch, would it float on the wings with the cabin submerged and me drowned or roll inverted with the weight of the engines?


There were multitudes of high wing aircraft long before airports that were called "flying boats"
Sort of started with Pan Am.
While they had sponsons on outriggers on the wing to prevent the wings from water contact, I do not remember any stories about sinking.

On the other hand I do remember video of the Ethiopian airliner, (767?), that was hijacked and ran out of fuel and ditched. It caught a wing low into the water while ditching and cartwheeled and disintegrated. There was a lot of loss of life even being a very short distance from shore and many volunteers to help with the rescue.

Okie
 
GalaxyFlyer
Posts: 1514
Joined: Fri Jan 01, 2016 4:44 am

Re: Ditching a high wing aircraft-would it roll inverted?

Tue Oct 16, 2018 3:08 am

One thing it wouldn’t do is roll over, wings will ensure that happen. Gear down likely pitchpole, though. The C-5 ditch modeling showed it would float somewhat nose low. IIRC, aft gear extended to act brakes on impact.

GF
 
crownvic
Posts: 2245
Joined: Wed Oct 20, 2004 10:16 pm

Re: Ditching a high wing aircraft-would it roll inverted?

Tue Oct 16, 2018 3:51 am

GalaxyFlyer wrote:
One thing it wouldn’t do is roll over, wings will ensure that happen. Gear down likely pitchpole, though. The C-5 ditch modeling showed it would float somewhat nose low. IIRC, aft gear extended to act brakes on impact.

GF


Wouldn't lowering the aft gear pull the nose down and cause a potential pitch-pole?
 
VSMUT
Posts: 2002
Joined: Mon Aug 08, 2016 11:40 am

Re: Ditching a high wing aircraft-would it roll inverted?

Tue Oct 16, 2018 6:50 am

It would typically settle upright with the wings floating on the water, and the nose protruding from the water. But thats assuming it doesnt break apart. Normally, before settling into the water, the aircraft should float tilting to one side, making the emergency exits on one side unuseable.

Erebus wrote:
What is a typical approach speed for a turboprop like the ATR or Dash 8?


About 100 to 110 knots. Depending on weight, you could go as low as 90 knots on the ATR 72, but it handles really poorly below 100, so we dont do it unless we really must.
The 42 is even slower.
 
SAAFNAV
Posts: 519
Joined: Wed Mar 17, 2010 5:41 pm

Re: Ditching a high wing aircraft-would it roll inverted?

Tue Oct 16, 2018 7:11 am

High wings certainly help this C-130 to stay afloat. As I've heard (but can't find sources for it now), they had to dispatch fighters to shoot/bomb it to sink.

https://pacaeropress.websitetoolbox.com ... 0b-7484237
L-382 Loadmaster; ex C-130B Navigator
 
WIederling
Posts: 6866
Joined: Sun Sep 13, 2015 2:15 pm

Re: Ditching a high wing aircraft-would it roll inverted?

Tue Oct 16, 2018 12:33 pm

Not a "full" highwing aircraft, but .. :
https://en.wikipedia.org/wiki/2009_Pel- ... d_ditching
Murphy is an optimist
 
pikachu
Posts: 141
Joined: Thu Feb 07, 2002 5:58 pm

Re: Ditching a high wing aircraft-would it roll inverted?

Tue Oct 16, 2018 8:01 pm

skipness1E wrote:
Sully showed that ditching a low wing airliner is possible safely. However if my day went wrong and the ATR or Dash 8 I was on was forced to ditch, would it float on the wings with the cabin submerged and me drowned or roll inverted with the weight of the engines?


Each dry engine is less than 1000 pounds.
 
EChid
Posts: 265
Joined: Fri Nov 03, 2017 4:00 am

Re: Ditching a high wing aircraft-would it roll inverted?

Tue Oct 23, 2018 3:08 am

Okie wrote:
skipness1E wrote:
Sully showed that ditching a low wing airliner is possible safely. However if my day went wrong and the ATR or Dash 8 I was on was forced to ditch, would it float on the wings with the cabin submerged and me drowned or roll inverted with the weight of the engines?


There were multitudes of high wing aircraft long before airports that were called "flying boats"
Sort of started with Pan Am.
While they had sponsons on outriggers on the wing to prevent the wings from water contact, I do not remember any stories about sinking.

On the other hand I do remember video of the Ethiopian airliner, (767?), that was hijacked and ran out of fuel and ditched. It caught a wing low into the water while ditching and cartwheeled and disintegrated. There was a lot of loss of life even being a very short distance from shore and many volunteers to help with the rescue.

Okie


My recollection on the Ethiopian flight was that there was an ongoing struggle in the cockpit which, in turn, caused the wing to tip and caused the disaster. But this fact doesn't change the statistics you're taking about.
2018: DRW-PER-HKG-ICN-MEL-AVV-BNE-OOL-SYD-YYZ-YYZ-YUL-YVR-PDX-SEA-SFO-PEK-KIX-CDG-IST-NRT-HND-BKK-FAT; AC J-TK J-OZ F-DL F-TG J/F-NH J/F-CX J-VA J
 
User avatar
TWA772LR
Posts: 6089
Joined: Thu Nov 17, 2011 6:12 am

Re: Ditching a high wing aircraft-would it roll inverted?

Tue Oct 23, 2018 5:51 am

EChid wrote:
Okie wrote:
skipness1E wrote:
Sully showed that ditching a low wing airliner is possible safely. However if my day went wrong and the ATR or Dash 8 I was on was forced to ditch, would it float on the wings with the cabin submerged and me drowned or roll inverted with the weight of the engines?


There were multitudes of high wing aircraft long before airports that were called "flying boats"
Sort of started with Pan Am.
While they had sponsons on outriggers on the wing to prevent the wings from water contact, I do not remember any stories about sinking.

On the other hand I do remember video of the Ethiopian airliner, (767?), that was hijacked and ran out of fuel and ditched. It caught a wing low into the water while ditching and cartwheeled and disintegrated. There was a lot of loss of life even being a very short distance from shore and many volunteers to help with the rescue.

Okie


My recollection on the Ethiopian flight was that there was an ongoing struggle in the cockpit which, in turn, caused the wing to tip and caused the disaster. But this fact doesn't change the statistics you're taking about.

As well as a lot of passengers having their life vests already inflated.
You know all is right is the world when the only thing people worry about is if the president had sex with a pornstar.


The thoughts and opinions shared under this username are mine and are not influenced by my employer.
 
User avatar
litz
Posts: 2183
Joined: Wed Dec 24, 2003 6:01 am

Re: Ditching a high wing aircraft-would it roll inverted?

Tue Oct 23, 2018 7:40 pm

Even worse for the Ethiopian 767, it caught an engine on a reef, which tore that wing from the fuselage. Instant structural failure and resultant disintegration, when the other wing flipped the plane over.
 
ELBOB
Posts: 72
Joined: Sun Jun 21, 2015 6:56 am

Re: Ditching a high wing aircraft-would it roll inverted?

Fri Nov 02, 2018 7:44 am

skipness1E wrote:
However if my day went wrong and the ATR or Dash 8 I was on was forced to ditch, would it float on the wings with the cabin submerged and me drowned or roll inverted with the weight of the engines?


Why would it roll inverted whilst resting on a more dense medium? If it doesn't have a tendency to invert whilst flying, it won't do so whilst floating...

Certification requires submission of ditching & floating modelling data, either physically or computationally obtained. That's also how manufacturers determine which doors to indicate for use on the safety cards. Check those and you'll deduce how the aircraft is expected to float, for high-wingers it's usually tail-down and one wing low.
 
T prop
Posts: 955
Joined: Tue Apr 03, 2001 4:33 pm

Re: Ditching a high wing aircraft-would it roll inverted?

Fri Nov 02, 2018 8:04 am

If I remember correctly, the very outboard wing box section on the old Dash 8's was sealed up with Orcon tape. The tape, that was applied during production, had printing on it that warned that it needed to be replaced if removed for any reason.
The purpose of the tape was to keep whatever wing that dropped into the water after a ditching water tight and afloat.
 
User avatar
trpmb6
Posts: 1426
Joined: Thu Apr 19, 2018 5:45 pm

Re: Ditching a high wing aircraft-would it roll inverted?

Fri Nov 02, 2018 3:39 pm

ELBOB wrote:
Certification requires submission of ditching & floating modelling data, either physically or computationally obtained. That's also how manufacturers determine which doors to indicate for use on the safety cards. Check those and you'll deduce how the aircraft is expected to float, for high-wingers it's usually tail-down and one wing low.


Came to post exactly this.

We sometimes have to minimize penetrations in certain areas of the aircraft based on ditching criteria. Bulkheads/Frames/Webs in the fairings under the fuselage are often riddled with system penetrations, but we must minimize them as much as possible to prevent water from flowing into other parts of the fairings if one should be penetrated and begin leaking. Similar to the titanic .. sort of.. and what I assume modern ship designs do as well.

All falls back to evacuation requirements set by the FARS.
 
CRJ900
Posts: 2266
Joined: Wed Jun 02, 2004 2:48 am

Re: Ditching a high wing aircraft-would it roll inverted?

Fri Nov 02, 2018 11:26 pm

The Q400 forward exits has ditching barriers that passengers must climb over when exiting the aircraft, so I assume the Q400 will theoretically float with one-third of the fuselage being below the water line.

There's at least one video on youtube showing the ditching barrier, I think it's a Q400 from airBaltic.
Come, fly the prevailing winds with me

Who is online

Users browsing this forum: harrisair, Jal1975, Starlionblue and 17 guests

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos