How to groundloop a flying boat

[pelmet]

Yes, it can be done.

Perhaps the experts here like a CL215/415 guy can tell why this happened.

https://vimeo.com/133906998

[ahramin]

I'm no expert, but they've got full left rudder during the ground loop.

[Rockie]

I'm no expert either, but I would think that large area - wide span surface on the bottom hull would be intolerant of anything but a wings level, even contact with the surface of the water. Lots of drag pretty far from the centerline if it digs in.

[Shiny Side Up]

Reportedly they'd hit some sunken debris, I think in another bit you see a boat lashed to it and guys bailing to get it to shore. Since it doesn't have floats on the wings, i'm guessing that if one of those sides starts taking on water, you hav some trouble keeping it upright.

Either way, one can only imagine the guy's would be changing their shorts after that merry-go-round.

[karmutzen]

They ran out of room on the lake and "pushed" it onto the water instead of maintaining the proper slightly nose up attitude and letting it settle in. Same as the Beaver on Lake Lovelywater in "MotherLode". Idiots.

[digits_]

They ran out of room on the lake and "pushed" it onto the water instead of maintaining the proper slightly nose up attitude and letting it settle in. Same as the Beaver on Lake Lovelywater in "MotherLode". Idiots.

What's the source for that information ?

[Meatservo]

I watched the video using the "pause" button to observe the landing in brief stages..., it seems to me looking at the elevator that the machine tried to porpoise on touchdown and the pilot got a bit behind the cycle and responded by pushing the nose down and digging it in a little too much. When this happens the centre of lateral resistance moves ahead of the centre of mass and makes a ground loop more likely. -Did I just sound like PDW there? Also the water looks like a breeze is coming from offshore but I don't see any crosswind technique being used... although it's hard to tell what the wind is doing, it looks pretty light judging by the flag on that boat in the background. Anyway what the plane did reminded me a lot of what happens when your copilot tries to land a Twin Otter on CAP floats in a crosswind without applying any corrective control inputs and you aren't paying as much attention as you should. Not that I've ever been in that situation.

[xsbank]

No flare, 3 busted Pratts!

[TG]

They ran out of room on the lake and "pushed" it onto the water instead of maintaining the proper slightly nose up attitude and letting it settle in. Same as the Beaver on Lake Lovelywater in "MotherLode". Idiots.

Thanks for your expertise

I suggest you take a look at the last picture showed in this link.
https://www.austrianwings.info/2015/07/ ... lfgangsee/

No need to understand their language to figure out that they hit something.
But just for you: "Baumstamm" translate as "tree trunk"

[Liquid Charlie]

Same as the Beaver

-- in my day that's how you stopped a beaver - most of float planes as well -- dig the floats -- checking back will not stop you as fast as might be required -- now dig the floats and the stopping distance is cut to almost nothing -- like anything else - it needs a little finesse - saved my ass a couple of times in short lakes --

These guys are lucky the hull wasn't opened up as if a can opener sliced through it -- happen in Greenland with a pig boat when the nose gear door peeled off -- inverted almost immediately and only 2 survivors out of about 18 people if memory serves ------

[PilotDAR]

I opine that this was a pilot failing. If they hit something, it was not big enough to actually cause the swing, a photo of the small tear in the hull was posted elsewhere. The aircraft touched down long and fast. I can't speak to how much room they had left, but perhaps the water loop was an attempt to stop. What I did see was full left rudder applied. That would cause a water loop, and is not accidental. If they got some reverse applied too, the aircraft was probably just about uncontrollable then. The reverse thrust takes the airflow off the tail, and makes it pretty ineffective, so once the waterloop started, the rudders and elevator would be useless to arrest it. I once used a bit of reverse on the step during testing, and never again!

A very expensive lesson for these pilots, and reminder to the rest of us, that we're not invincible!.....

[Liquid Charlie]

Regardless of what happened when I look at that aircraft it appears to me that it's a poorly designed hull with very little pronounce keel and what we see on the video is part of it's nasty little habits -- clip the wings and turn it into a WIG

[Meatservo]

Well, it is a little old-fashioned, but that model (and the exact plane actually) was an extremely successful open-ocean flying boat used all over the world. In fact a few Dutch ones ordered pre-war found themselves doing combat against the Japanese navy, in the hands of the RAAF. One of the few types to be used in combat by both sides of the conflict.

Not bad for a poorly-designed hull! Also doesn't look too much different than the modern Dornier push-pull seaplane with 228 wings, forget what it's called at the moment.

[PilotDAR]

I expect that the flatter V/shorter keel is necessary, otherwise the wheel gear would have to be very tall. It's great to have very deep V hulls for ocean going flying boats, but it becomes a challenge when you have to get gear legs down around it...

That said, the Dornier seemed to be landing in entirely acceptable water conditions, so it should not need a keel to keep it straight, the pilot should do that!

[GyvAir]

Found another photo that wasn't in the write up showing more damage directly opposite on the left side of the keel as well. Nothing really indicating definitively what station the damage is at, but I'm guessing just fwd of the cockpit. Pretty tough to say which is cause and which is effect though.

[Meatservo]

Boy. Sure looks like it whacked something big, doesn't it?

[TG]

Worth mentioning:
http://aviation-safety.net/wikibase/wiki.php?id=178034

During the airshow "Air Challenge 2015" the Do 24 ATT was going to perform a "touch and go" display on the lake.

[PilotDAR]

Boy. Sure looks like it whacked something big, doesn't it?

That wasn't my thought. At most, I think he whacked something rather small, and perhaps painted white, resulting in a white smudge seen just in front of the top of the tear on the right side. Perhaps he applied a boot full of left pedal to attempt to avoid it, but the bottom line is a lot of left pedal was applied and held, and at speed, that far forward on the step, it caused the plane to go around.

If a [deliberate] waterloop has prevented a more damaging event, so be it, but there is still a lesson for water pilots, particularly flying boat pilots here, that control can be lost. That said, you gotta like flying boats for this, 'cause this waterloop done in a floatplane would have been a very much more serious event!

[Liquid Charlie]

I have no experience with "water" loops but I do know about ground loops having preformed several to stop an aircraft after lose of breaks -- the dynamics are that at some point in the ground loop you must assist the aircraft in the turn to tighten the ground loop so when you are going through 180 about degrees you can tap the engine(s) and the aircraft stops - obviously it's all about timing but the worst thing you can do is fight a ground loop - after watching the video and the rudders in particular it appears to me he intentionally fed in the full rudder after it became apparent the aircraft was past a recovery -- and it worked -- the aircraft did not sink - now if it was bull sh1t luck or by design -- only the crew will know for sure -- no matter what is said

[GyvAir]

When you translate one of the news stories from german, you get this: “Eyewitness Christian Hetzenauer tells of a conversation with the pilot Iren Dornier. Within a split second, the crew would have been up to his waist in water. By Hand scooped Dornier water from the cockpit.”

I’ve never seen it personally, but I’ve heard of hull punctures at high speeds resulting in cockpit and cabin floor panels bursting upwards from the water inrush. Makes me wonder if the pilot even still had his feet on the rudder pedals as it went around.

One thing I noticed watching the slow motion version is that at about 47-49 seconds, as the plane is approaching about 45 degrees rotation, the rudders appear to suddenly swing hard over and flop against the LH stops a bit, though the plane is definitely already turning left by 43-44 second mark.
(Probably trick of the light though)

[TG]

When you translate one of the news stories from german, you get this: “Eyewitness Christian Hetzenauer tells of a conversation with the pilot Iren Dornier. Within a split second, the crew would have been up to his waist in water. By Hand scooped Dornier water from the cockpit.”

I’ve never seen it personally, but I’ve heard of hull punctures at high speeds resulting in cockpit and cabin floor panels bursting upwards from the water inrush. Makes me wonder if the pilot even still had his feet on the rudder pedals as it went around.

Yes, that's probably what happen.
Sounds a bit more realistic than the morning quaterbackl lynching like: "no flare, 3 busted pratts!" or "pushed it onto the water Idiots"

[Caracrane]

log magnet or what? From the pictures I see from you guys that hull has been damaged more than once...........

[J31]

Maybe they hit something...... But the crash sequence started with a faster than normal landing, a tail wind and the nose low. On touchdown the long flat hull dug badly with no correction, in fact they allowed the nose to further drop at touchdown and around she went. Check out this and other youtube video's that show a more nose up touch down.

https://www.youtube.com/watch?v=4THHTczGD9k

I think the damage was done by extreme water force on the hull during the "water loop". It would not surprise me that more damage was done to the fuselage.

There seems to be a lack of experience operating this aircraft.......here it is running over a Zodiac

https://www.youtube.com/watch?v=z11yqU6ubE8

[TG]

Maybe they hit something...... But the crash sequence started with a faster than normal landing, a tail wind and the nose low. On touchdown the long flat hull dug badly with no correction, in fact they allowed the nose to further drop at touchdown and around she went.

I'm going to give up defending this crew from the lynching mob very soon.

It's not maybe. They hit something and got a puncture!
Probably right at touch down or very soon afterward (water gushing inside)

You will try to keep nose up or just any kind of controls when tons of water rushes inside your cockpit.

[xsbank]

We'll TG, I am very pleased you have chosen an opinion out of all of these above that agrees with yours.

I stand by my comment. No flare, 3 busted Pratts. Approach was too low, unstable. You would never fart around like that landing on land, why do it here? You are supposed to leave yourself an 'out,' if he was getting too near the end of the lake with nowhere to go, he pooched it.

If he hit something he did not check over his landing spot before he committed, but how could he see anything with that crap approach?

No flare, busted... you know.