Air NZ emergency at Woodbourne

[corsair67]

a guy at work said he say it on the news with them lifting the plane up and it's undercarriage came down as it was shifted.

I'd imagine that a belly landing would be enough to loosen up a jammed undercarriage in a lot of cases?

[beagle]

So you are saying it was probably some sort of FOD in one of the undercarriages that jammed it in the up position.

[Bruce]

Dont mention FOD in the undercarriage bays... one of Eagles Previous wheels up was caused by a nice big Mag Lite Torch - did a lot of damage to the undercarriage, nothing to the torch (which even had the "ex" engineers initials on it!)
This would be the 4th Eagle wheels up by my count:

late 1980s, Bandeirante Wheels up Palmerston North after mainwheel fell off on approach (Pilot elected to land wheels up)
early 1990s Bandeirante Wheels up Auckland - Torch in UC bay
circa 2000 Metro Wheels up Hamilton due broken drag link (Manufacturing / overhaul fault)
2007 B1900 Woodbourne, cause?

Nothing much in common between any of the previous incidents....

[Dave Homewood]

Wasn't there a Bandeirante wheels up in Hamilton too? I have the huge photo from the Waikato Times somewhere. I might be thinking of the Palmy one, but I thought it was at Rukuhia. The photo showed it about a foot off the deck, gliding in. Did very little damage.

I wonder if something could be done to stop damage in a wheels up, like some sort of dolley they can put down on. Or foam mats or something. Has anyone tested such an idea?

[corsair67]

If I recall correctly, the Thunderbirds (Gerry Anderson - not the USAF ones!) landed Thunderbird 3 (? - the big green thingy) on the back of a huge truck when it had some problem in one of the episodes! ;D

[amitch]

corsair67 said:

If I recall correctly, the Thunderbirds (Gerry Anderson - not the USAF ones!) landed Thunderbird 3 (? - the big green thingy) on the back of a huge truck when it had some problem in one of the episodes! ;D

Maybe there's no trucks large enough in Blenheim ;D

[Bruce]

The RN Fleet Air arm tested a "Rubber Deck" concept in the 1950s, sucessfully landing a Seahawk and a Sea vampire on a specially prepared padded rubber surface (at Lossiemouth I think) At the time they were investigating ways of saving weight as the early jets were lacking in power. They thought of catapult lauching the aircraft off special trollies and landing them back on the rubber deck, enabling them to dispense with undercarriages altogether. the difficulties of ground handling the aircraft and the improvements to engine design meant that the idea was abandoned.

[fletcherfu24]

Be interesting to know what the repair bill is ?,one would expect little change from $1million bucks.

[Radialicious]

No Dave, it wasn't me thankfully. The process of actually putting the aircraft on the runway and stopping it safely wouldn't be beyond any of our crews. However, to do it as well as it was was a bloody good effort. If I was on board when it happened, I would be glad that that certain captain was at the helm. The landing (and what a beauty it was) would probably be the most certain phase of the whole episode. Before and after would be when most of the questions would be asked.
The Beech 1900 protects itself from a wheels up landing with a healthy number of on board systems and what was thought to be a failsafe gear extension system. Also, the retracted gear protrudes slightly from the wheel wells so that a belly landing is not quite that. Imagine a Yak-52 landing with its wheels up. That is fairly similar. The aircraft isn't designed to be landed in that manner but if it does, she will fly again without a great deal of drama.

[flyjoe180]

There's some close ups of damage photos and some comments from an engineer regarding repair costs etc on these links (filtered out the rest of the replies, most of it is just the usual pprune crap):

www.pprune.org/forums/showpost.php?p=3356795&postcount=50
www.pprune.org/forums/showpost.php?p=3357507&postcount=58
www.pprune.org/forums/showpost.php?p=3359803&postcount=71

[Dave Homewood]

Thanks for that Al. Can you confirm what the prop blades are made from please?

[Radialicious]

They are a Kevlar reinforced plastic. Outside of the Kevlar is a thin steel mesh. The leading edge is a nickel strip and the rest is a paint job. If we park the Beech across a strong wind, the whole prop flexes in the gusts.

[greaneyr]

The 1900s are one of the few remaining turboprops in our skies with a low-wing these days. I'd hate to think what would happen if they had to make a wheels-up landing in an ATR or a Q300.

Can anyone shed any light on this? Would it be any more dangerous to make a wheels-up landing in a high-wing a/c?

[Dave Homewood]

Thanks for that about the props Al. No doubt in the case of a belly landing they're kinder on the engines than metal props would have bee,

Interesting question Richard.

[Radialicious]

A wheels up in a high wing machine wouldn't be as predictable as a low wing one. The ATR for example has quite a bulbous fairing under the belly that contains the retracted gear. Hopefully that would get demolished and the undercarriages inside would provide a stable footprint and prevent a wing drop as the speed washed off. The Dash-8 would probably be a write-off as the entire underbelly would contact the runway. Directional control would be impossible once a wingtip contacted the ground and stopping distance would be anyones guess.
At least the 1900 still rolls on its wheels and braking and very limited steering is available.

[greaneyr]

radialicious said:

The Dash-8 would probably be a write-off as the entire underbelly would contact the runway.

The last Dash 8 that had the problem of undercarriage not lowering in NZ certainly ended as a write-off. One thing I've always wondered is why they don't do wheels-up landings on something a little softer than a runway. I'm sure there's a reason.

[FlyNavy]

One answer (probably among many other factors to be considered for each aircraft type and configuration) would be that a runway surface has known factors for a soft landing upon it. However a grass or unprepared runway has many unknown factors particularly if the ground is soft from rain or other issues like drainage ditches and the like.

In a crash it is the 'sudden stop' that gets you so sliding along a hard runway to slow down gradually is not a bad thing (after a soft flared landing). However coming to a sudden stop in a drainage ditch or mud puddle or whatever on an unprepared surface may not be so ideal for passengers or aircraft.

There would be many variations on this 'non runway emergency landing' including whether to land on a flat sea, along the swell or into the wind etc. In an emergency there may not be time for any other consideration other than to get the aircraft on the ground as best one can in a clear area.

[Bruce]

On the Bandits I am familiar with, and I would assume other aircraft with low slung engines, the manufacturers recommendation is to land wheels up on seal rather than grass. On grass, the aircraft will tend to dig in, especially the engine intakes. This twists the wing and could lead to the aircraft breaking up. A hard surface restricts the damage to those areas in contact.
That said however, tha Bandeirante was one of the few aircraft with an emergency UC RETRACT mechanism. it was designed for overrun situations on short mountain airstrips, the gear would almost instantly retract, without opening the forward doors, in order to slow the aircraft down in a real hurry (with associated damage, but hopefully saving lives...)

[lumpy]

Apearantly the Argosy that went on its belly at Woodbourne had dirt and grass in places that you would never believe dirt and grass could get , those that saw it say it would have been very easy to imagine it "digging in ". Maybe thats why they report on how far off the centre line of the run way the plane was ( ie how close to disaster ? ) ( I think from memory the Argosy slid off the run way )

[flyjoe180]

The Metro manual and QRH recommends landing on seal or hard runways for a wheels-up landing and also suggests the possibility of shutting down one engine once a landing is assured. Would be a rough ride, the Garrets have a fixed shaft and the props are steel.