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View Full Version : F8F: only airplane with sheddable wingtips?


stepwilk
30th Nov 2009, 13:09
As many of you will remember, the Grumman F8F Bearcat was originally designed with outer wing panels that broke off if 7.5Gs were exceeded. Then to prevent asymmetric wingtip shedding, the panels were installed with primer cord along the seam, to blow the recalcitrant tip off if one went away. Finally, the whole idea was given up as unworkable. (It worked during well-controlled test conditions but proved to be risky otherwise.)

Question: Was there ever another aircraft with such a designed-in failure mechanism, whether wingtips or some other component?

The only one I can think of was that Dornier-like rear-engine Saab fighter that had a mechanism to blow off the entire propeller if the pilot needed to bail...which ultimately led to the Swedes inventing the ejection seat. (No, not the Germans nor the Brits...and it wasn't even Volvo.)

Agaricus bisporus
30th Nov 2009, 23:16
Well, iirc the F8 Crusader had the opposite system that allowed the odd pilot to get airborne without his wingtips, indeed without the better part of his wings...yet with skill and some luck they could (occasionally) be reinstated later in flight.

To complete the "opposite" theme this was considered too risky to be tried under test conditions, but sometimes worked under uncontrolled (!!) operational circumstances.

ps

Couldn't the Mitsubishi MU2 be described as a "designed-in failure mechanism"?

Atcham Tower
1st Dec 2009, 08:22
I believe that the twin-engined Dornier 335 fighter which had a propeller at both ends of the fuselage was able to jettison the rear one to enable the pilot to bale out more safely. Few entered service by the war's end. I also once read, but have never been able to confirm, that the Ju 87 Stuka could blow off its fixed undercarriage legs if a crash landing became necessary on rough ground.

Schiller
1st Dec 2009, 09:15
The Seamew, too, had an u\c that could be jettisoned before ditching.

Mechta
1st Dec 2009, 10:42
The Rutan Voyager shed its wingtips as it took off for its round the world flight...:} Definitely not what Burt or Dick intended though.

IIRC One of the gullwing PZL fighters had a jettisonable internal fuel tank in case it caught fire!:eek:

Atcham Tower
1st Dec 2009, 11:03
This is getting quite fascinating!

sandiego89
1st Dec 2009, 15:30
The Kamov Ka50 has exlplosives to shed the rotor blades before the ejection seat fires. Otherwise ejecting upwards could ruin your whole day :}

stepwilk
2nd Dec 2009, 00:16
Keep 'em coming! You guys are a fascinating resource, and the depth of your experience and knowledge always amazes me.

An to think I have MU2 time...too young way back then to realize I was potentially self-destructing.

Krakatoa
2nd Dec 2009, 04:33
I could be wrong and with an old mans memory but I thought the Bearcat
had folding outer wings.

Alan Biles
2nd Dec 2009, 11:47
Not sure it was a designed mechanism but I remember watching, fascinated, as a wing tip peeled off an ADC B.727 between Calabar and Lagos. It took about 10 minutes in all and finally departed company with the rest of the aircraft as the slats went out on finals.

I pointed it out to Captain after we'd landed and after he'd had a look, he jumped in and flew back to Calabar.:eek:

stepwilk
2nd Dec 2009, 12:18
Some (I don't think all) Bearcats indeed did have manually folding wingtips--simply hinged to fold up and in, nothing fancy like on the F6F. They were manual for weight-saving, as was the tailhook: it would deploy (gravity) but had to be muscled back into place, and if you've ever hefted a tailhook, you'll know that's the right word.

Anyway, the outer six feet of the F8F wing was foldable, but the blow-off panels were the outer three feet. If you lost the entire fold-up part, you'd lose the entire aileron too. Not good.

treadigraph
2nd Dec 2009, 12:35
I can't think that I've ever seen TFC's long-time resident Bearcat with the wing-tips folded, but the second aircraft they operated for a while certainly did have them; it returned to the USA and joined Bill Anders' collection.

Anybody remember the superb pairs display by Steve Hinton and Paul Bonhomme at Flying Legends about 10 years ago...?

JEM60
3rd Dec 2009, 19:43
Of course!!!!!. Displays like that never get forgotten!!!. Not sure what to expect from TFC next year, anyone with any updates???

Brian Abraham
7th Dec 2009, 12:11
Stumbled on this by accident. The test pilots story of the F8F sheddable wingtip development. Clipping the Bearcat's wing | Flight Journal | Find Articles at BNET (http://findarticles.com/p/articles/mi_qa3897/is_199808/ai_n8826530/?tag=content;col1)

Double Zero
7th Dec 2009, 14:57
Well, the Harrier 1 ( i.e. all-metal, GR1-3 & Sea Harrier ) had optional ' ferry tips ' which could be fitted for extended range, I believe limited to 3.5G, certainly by my time no-one bothered with them, even on the epic GR3 flight to Ascension in 1982 ( there was a higher ' ferry ' engine oil level which certainly was used though ).

These tips looked like a good bet of coming off (or becoming 'winglets' !)in the case of any vigorous manouvres, which may be one of the reasons they weren't used; obviously J.Farley's input would be useful on this one, as ever.

henry crun
7th Dec 2009, 20:08
Brian: If you can lay your hands on a copy I can recommendCorkey Meyer's book "Flight Journal".
The sub title is "A test pilot's tales of dodging disasters - just in time".

Brian Abraham
8th Dec 2009, 01:35
Much obliged Henry. I'll put it on my Xmas wish list for Santa.

treadigraph
8th Dec 2009, 06:56
Blast you Henry, that's more money spent! :ok: