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Aircraft Certified for Ditching

Aircraft Certified for Ditching

Aircraft Certified for Ditching

(OP)
Where is the official location of the certification of an aircraft for ditching? 14 CFR 25.801 starts with "...(a) If certification with ditching provisions is requested..." so it must be requested. How do I know which aircraft have been requested and certification granted? Is it listed on the airworthiness certificate? Is it in the operation specifications for the owner/operator? Is it listed in the airplane flight manual?

I could not find it in the TCDS. The TCDS of course contains 25.801 in the certification basis of a typical transport category (14 CFR Part 25) aircraft, but 25.801 also requires that a number of other regulations must be complied with to certify for ditching. Since certification for ditching is an option that must be requested, if I were an FAA inspector (I am not) looking at the data for a specific aircraft serial number, where would I look to find the official status for ditching certification?

RE: Aircraft Certified for Ditching

25.561.

yes, the verbage is awful ... it's being going downhill for a while. If you're showing compliance to 25.801, then you are requesting "certification with ditching provisions".

"all" major transports (all commercial transports ?) comply with 561 and 801.

another day in paradise, or is paradise one day closer ?

RE: Aircraft Certified for Ditching

(OP)
rb1957 thanks that is certainly part of the requirement as 25.561 does state that landing on both land and water must be considered. However, I think my answer is the Operational Specifications, though I have not been offered a look at those yet.

After reading your response I was inspired to do more general digging rather than looking just at 25.801. Two other examples of aircraft capabilities that are designed into an aircraft that are not automatically authorized for an operator are Category III Autoland, and ETOPS. Both of these capabilities may be designed into an aircraft, but the FAA requires more than just the aircraft have the capability. Special maintenance programs for reliability monitoring, special training for maintenance technicians and flight crews, etc., must be shown to the FAA to obtain Category III Autoland and ETOPS approval, and those are in fact listed in the Operational Specifications for each specific owner/operator. I am willing to guess at this point that I would need to review the owner/operator Op Specs for the airline we are contracting with to find if they are approved.

Thanks for pitching in!

RE: Aircraft Certified for Ditching

(OP)
Well I am still inspired and digging. (Thanks rb1957) For anyone else who might care to know, FAA Order 8900.1 Volume 3 Chapter 18 governs Operational Specifications. It appears that under Op Spec A013 that deviations to the ditching capability for a specific owner/operator are addressed there. This has been a good learning experience for me.

RE: Aircraft Certified for Ditching

it is truly amazing what you can find ! not a snipe, my own journeys into the "Backwoods" of certification were the same.

You've gone out of my area (being certification of design rather than operating rules). But these operating rules shouldn't define the certification standard for ditching (IMHO) ... that should be in FAR25. Operators can (by the sound of it) opt out of some of these requirements (if they never fly over water ?).

another day in paradise, or is paradise one day closer ?

RE: Aircraft Certified for Ditching

The Type Certificate Data Sheet (TCDS) is your source. If the aircraft model is certified for ditching, it will say so (Order 8110-4C, Chapter 3, paragraph 3-3.b.(22)(c)). Some more recent TCDS's will even say if it is not, for instance, on the Cessna (oops, Textron) model 680: "14 CFR 25.801 ditching not complied with."

There are also models partially certified for ditching and the TCDS will list the missing pieces. Usually equipment (rafts, lifelines, life vests).

The pieces leading to 25.801 certification are:
25.563 structural
25.807 exits
25.1411 equipment
25.1415 ditching equipment
25.1585 operating procedures

It would be difficult, but not impossible, for a party other than the OEM to do ditching certification. It would require an STC since it obliterates a TC limitation. The structural and flotation can be done by analysis, or testing in a model basin. This would inform the AFM or AFMS on landing speeds and attitudes, flaps up/down, and what to do after. Many airplanes have doors that would be below the waterline after skimming to a stop, so those would be placarded as such near those doors. Aircraft with split doors (Lears, Falcon 10) only open the top half. Others have a "ditching dam" installed that serves the same function. The aforementioned model 680 had an ELOS on that topic - evidence that ditching certification was partially attempted.

If it is an equipment issue, or certification is ambiguous, it's a simple matter of document and equipment evaluation (slide/rafts, or just slides) to bring it up to snuff. Just compliance findings, STC not necessary.

Ops Specs - can't help you there.

RE: Aircraft Certified for Ditching

(OP)
Thanks to all for the input. I am always better informed when I read Eng-Tips.

RE: Aircraft Certified for Ditching

This is interesting...and sooooo different from military: crash worthiness/survivability testing or 'simulation/analysis' for land and water mishaps is 'built-into' DoD/MIL aircraft qualification specs... with the rare exceptions having to be fully justified based on other modes/means of survival [like ejection or bailout].

Likewise, other damage scenarios must be validated for basic survivability and mission completion, such as low-level/high-speed/heavy bird-strike, battle damage, tire/landing gear failure and crash survivability, etc.

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: Aircraft Certified for Ditching

(OP)
Excellent point, Wil. The military has the unlimited authority to crash into any type of terrain! cyclops

RE: Aircraft Certified for Ditching

And there are likely more MIL aircraft [fixed-wing and helos] on the ocean sea floor than metal-hulled ships and subs. I have personally been on 3 mishaps where jets were lost at sea: we recovered [2] from shallow/bay-water... left the 3rd in the middle of the North-Pacific ocean in 'Davy Jones's Locker'... some (-)7000Ft below sea level.

Vultures 'punch' way-above their weight and make godawful messes at 650Kts [BONE laminated polycarbonate windshields are over 2-inches thick [measured 90-deg thru the thickness]... and are highly angled which spreads-out/absorbs the impact forces of these creatures. Even 'just' a #4 bird hitting a wing or stabilizer leading edge at 250-Kts can cause amazing/expensive damage.

And fixed-wing runway mishap departures are preeeeetty common.

And the places/reasons/'ways' for helos crashes have mind-boggling variety.

Generally speaking, 'survivable impacts/crashes' should provide the precious aircrew 'a survivable environment' for escape to safety... and where possible... save as much of he aircraft as practical for salvage.

Go to YouTube for ghastly videos of crashes.

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: Aircraft Certified for Ditching

OH, yeah... one general aviation website posted the question...

You have sudden engine failure over forested terrain dotted by lakes and rivers. You are forced to make a choice: [a] 'land' in the treetops or [b] ditch is one of the lakes or into a river. WHICH choice is the 'best one' for survival?

PS: activating Your CAPS airframe parachute was not an option.

I made a choice... WHAT ARE YOUR CHOICES?

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: Aircraft Certified for Ditching

I don't know, and I don't remember if my instructor ever covered this.
I've never done underwater egress training. Maybe they have something to say about the odds of success with various water landing scenarios.

Depends on the configuration of plane, I'd say...
Retractable gear, high wing - go for water. Has a better chance of skimming in on the belly before doing a nosedive into the water, and it will not be going as fast when it does flip over the nose.
Fixed gear - forget the water. You'll be flipped over so fast as soon as you hit at 50 knots that you could be knocked unconscious - no amount of egress training will help you.
I assume you're talking about common GA aircraft types, low and slow enough that an airport 100 miles away isn't an option like it is with a commercial jet.

Also... in water, crack open any doors you can reach. In bush, leave the doors locked.

RE: Aircraft Certified for Ditching

Its very airframe terrain dependent & involves a truck load of luck.

If one thinks of that flat country with small trees its easy but around here its more likely to be a narrow valley with trees on steep ground and a deep lake. Attempting to land up hill into trees is going to get messy really fast.

Gull doors on the cockpit should be left closed even for ditching, why because if they are open it gives another edge to bash your head on (this comes from the ditching of an aircraft on a ferry flight about 200 miles short of Hawaii, being a non US citizen the coast guard swimmers didn't jump to attempt to fish him out).

How wimpy are the trees, how long before someones coming to get you, I know a couple of guys who got a tad low ridge soaring and clipped a tree, ending up upside down in the tree, 50 ft off the ground till they got rescued. Never did find out how they got the glider out of the tree.

There was a glider out landing fatality local where the pilot attempted to ground loop instead of going through a fence, ended up with a fence post coming through the side of the cockpit. Even small trees can be fatal if you can't manage to crash between the trees all the way in (guess that means plantation trees are better than wild tree).

The shore line / shallows is typically the best bet, but it really is, the good options are long gone & none of the bad options look slightly appealing.

RE: Aircraft Certified for Ditching


interesting, only because the question was asked ... from the Gulfstream GV (and pretty much any Gulfstream) Type Certificate

Compliance with the following Optional Ditching Requirements has been established:
Data covering ditching requirements of 25.801, including 25.563, 25.807(d) and
25.1585(a) (but excluding 25.1411) are approved. When the operating rules
require emergency ditching equipment, compliance with 25.1411 and 25.1415
must be demonstrated. Gulfstream Report 1159-GER-7 entitled "Outfitting
Requirements for FAA Certification for Ditching" provides an acceptable
means for showing compliance with 25.1411 and 25.1415

another day in paradise, or is paradise one day closer ?

RE: Aircraft Certified for Ditching

IIRC, that's a kit that allows a "ditch switch" to close the outflow valves of the pressurization system so that they don't admit water.
Other ditch-switch mods include an inflatable dam around the emergency exits, because the doorways are below the waterline when "afloat".
When Sully told his story, he did have the presence of mind to use it.

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