Why no rollbars....?

[wyhdah]

I've never really thought too much about it but why don't some of the all out race planes have a roll cage in the cockpit? I know it wouldn't help in a high speed accident but an accident on the runway would shurely be more survivable.

Maybe it is mute but they sure seem to help in the other motorsports disiplines and there have been some 50g impacts that those guys have walked out of. It looks like some of these rollovers should be survivable without just luck.

I think the planes with the turttle decks could put a roll bar behind the pilot that could be fairly stout without even being seen much less obstruct egress and ingress.

Just a thought for the pros.

[Leo]

Re: Why no rollbars....?

I had read in an article on th RB-51 that Browning had reinforcement put in the floor and seat of the RB when it was built. If so, sure seemed to help.

[wyhdah]

Re: Why no rollbars....?

I knew of two Agcats, that plane is mildly roll bared, that hit head on flying low at the middle of an airfield. I won't go into how that happened but it was practically a prop to prop collision and both pilots walked away. Those are tough planes.

I guess my point is almost all other motorsports have some type of driver/pilot protection except the fastest one. Isn't that a bit strange?

[FlyinLo]

Re: Why no rollbars....?

It isn't an unlimited, but my race biplane "Miss Gianna" was in fact designed with a roll bar of sorts in the turtledeck. It is some triangulated fuselage tubing that reaches up to the high point of the turtledeck right behind the cockpit. Between that and the bridge girder pylon that the upper wing is mounted on, flipping the airplane over on the ground should be survivable.

[flyingjibus]

Re: Why no rollbars....?

Sorry to hijack but everytime I see Mr. Lo post on here I am reminded of that incredible peice of flying I watched you do. I know you probably dont think of it as such but that is a happy memory for me. Good job!

[FlyinLo]

Re: Why no rollbars....?

Just keep pointing it away from the brown stuff so as not to test the structural strength on impact...

[wyhdah]

Re: Why no rollbars....?

It isn't an unlimited, but my race biplane "Miss Gianna" was in fact designed with a roll bar of sorts in the turtledeck. It is some triangulated fuselage tubing that reaches up to the high point of the turtledeck right behind the cockpit. Between that and the bridge girder pylon that the upper wing is mounted on, flipping the airplane over on the ground should be survivable.

That is exactly what I had in mind. Part of the problem, to me, is the engine often separates from the fuselage and the next point of roll is the cockpit to tale. If the engine says on there might be a small area from nose to tail but if it's gone pilots head is the highest point.

[wyhdah]

Re: Why no rollbars....?

It isn't an unlimited, but my race biplane "Miss Gianna" was in fact designed with a roll bar of sorts in the turtledeck.

Oh, and you'll notice I said race planes but your plane would qualify. I really meant to leave out the family planes. The problems with a rollbar would be the same as the family car.

[FlyinLo]

Re: Why no rollbars....?

I dug out one of the old construction photos from before the turtledeck was installed. You can see the triangulated tubing behind the cockpit as well as the upper wing pylon. Hopefully I never have to rely on that rollover structure...

[Apteryx]

Re: Why no rollbars....?

In F1 standard Cassutt's have somewhat of a roll structure, as do Shoestrings. Sometimes these are removed when the turtle deck is cut down. In Endeavor, there is stout roll over structure, built into the head rest/bulkhead assembly.

Paul

[team zipper]

Re: Why no rollbars....?

From the Formula One Technical Rules:
Paragraph 7.1 states:
Substantial protection for the pilot other than the fin must be provided either fore or aft of the pilot cockpit. The structure must not obstruct forward visibility.
So, effectively, Formula one racers have roll bars or some structure to protect the pilot in event of a tip over. But that's about all. My ZIPPER, Ra ce Number 1, has 3/4", thich walled 4130 steel tubing in a pyramidal structure right behind my head.
cheers...Zip Andre

[Skyracer]

Re: Why no rollbars....?

T6's have a rollover structure behind the pilot's head required to be in place by the class technical rules.

[number17fan]

Re: Why no rollbars....?

Here's a photo of part of the turnover structure of an Air Tractor 802. The helmet the pilot is wearing is not DOT approved! A 15lb turkey vulture will break this type helmet even after slowing down on its way through the windscreen.

[wyhdah]

Re: Why no rollbars....?

Here's a photo of part of the turnover structure of an Air Tractor 802. The helmet the pilot is wearing is not DOT approved! A 15lb turkey vulture will break this type helmet even after slowing down on its way through the windscreen.

That picture shows a full cage structure. X braces in over the pilot, K braces behind and bars in, what it would be called on cars, A pillar. That plane is built for crashing. This would be prohibitive to the canopies the race planes run but a partial structure behind the pilot is completly doable I believe.

[wyhdah]

Re: Why no rollbars....?

His is a picture of one of the drag car chassis we build here. You can see the kind of car it winds up in behind the bare chassis. This chassis is a 69 camaro but the concept is the same.

Pay close attention to what SFI calls the Funny Car cage. It is directly over the driver. Many chassis are built with only this structure over the driver. I think something like that would benifit a raceplane.

This chassis is certified for a crash weight of 3000 lbs at 200+ mph. They actually cert. chassis on time in the quarter mile but you get the picture.