RV 7 slider

Hi all, I have almost 300 hrs in a RV 7 tip up and love it, am building a -7 slider that should fly early next year with a little luck.
My Question is has anyone ever opened a slider in flight or flown with the canopy off ? Opening it maybe 12-18? would be best but I?m wondering about pressure on the underside of the plexi or adverse elevator or rudder effects
I imagine this has been discussed but didn?t find anything in a search.
Thank you
Dave

I opened the canopy in flight at around 100-120 KIAS just to see if it?s possible in case I have to jettison the canopy. It can be done however the aerodynamics try to close it. I would not suggest to fly the plane with open canopy, it is then not locked at the rear and we don?t know what the air pressure will do at the higher speeds.

SuperCubDriver said:

I opened the canopy in flight at around 100-120 KIAS just to see if it?s possible in case I have to jettison the canopy. It can be done however the aerodynamics try to close it. I would not suggest to fly the plane with open canopy, it is then not locked at the rear and we don?t know what the air pressure will do at the higher speeds.

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Yeah, the little plastic slider block that runs on the track is not exactly designed for air loads. But as long as the air loads are downward, which experiences seem to suggest they are, it is not going anywhere.

The question would be if there is some speed or flight attitude where the loads could reverse and try to lift the back of the canopy upward. I don't know. And different canopy shapes will likely behave differently. We know from Jon Thocker's reports that the RV-8 canopy maintains significant download. Enough so that he found that it depressed the skin and the track in the span between fuselage bulkheads and he added another bulkhead to support it. But the RV-7 canopy might lift upward, I don't know.

There was a video sometime back of someone flying a 7 with the canopy off and someone skydiving from it. I think the video was taken down though.

I'd be concerned that the opening of 12"-18" (basically 3/4 of the way or more open) could result in it departing and hitting the tail. Also, how would it effect airflow over the elevator and rudder?

Not something I'd really want to experiment with -but YMMV.

if the canopy is slid aft only a couple inches, that gap will be exposed to a lower static pressure air stream as is comes over the top of the front wind screen. the gap air pressure affects the entire lower side of the canopy by exposing it to this lower pressure and thus will try to move the canopy forward and downwards. if the canopy is opened more (by how much I don't know) the pressure will reverse.

Steve Melton said:

if the canopy is slid aft only a couple inches, that gap will be exposed to a lower static pressure air stream as is comes over the top of the front wind screen. the gap air pressure affects the entire lower side of the canopy by exposing it to this lower pressure and thus will try to move the canopy forward and downwards. if the canopy is opened more (by how much I don't know) the pressure will reverse.

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I think the narrow channel between the aft portion of the canopy and the fuselage skin will create a tremendous venturi, so there should be a lot of suction back there, even if the forward portion of the canopy does fill up with elevated pressure in the cavity.

But I don't really want to find out.

AG-pilot said:

Hi all, I have almost 300 hrs in a RV 7 tip up and love it, am building a -7 slider that should fly early next year with a little luck.
My Question is has anyone ever opened a slider in flight or flown with the canopy off ? Opening it maybe 12-18? would be best but I?m wondering about pressure on the underside of the plexi or adverse elevator or rudder effects
I imagine this has been discussed but didn?t find anything in a search.
Thank you
Dave

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Van's is adamant that RV's are not designed to be flown with canopies open or off. Just call them.

Just had a co worker die in a Mustang II when the canopy opened in flight. It departed, tore off part of the tail, and the plane went in vertical. It also killed a 13 yr old son of another coworker. Pilot was a national aerobatic champion with 11,000 hours and part of the twin tigers air show team. I have a 6A and would never attempt to open or partially open a canopy in fight. But that?s just me.

Kurt

RV7 slider

Thanks all for the replies. I should have indicated this would be in relatively slow flight, 70 or so would be my target speed and maneuvering slightly for pictures.
I agree the rear slider block looks kind of wimpy if there was much lift applied I can see how it could let go of the rear which could be bad. I could maybe work in 10-12 inches of opening it just would require more passes.
Anyone beef up the rear slide? I have the slide extension but thought I could install pins to limit aft movement and maybe pin it back in place once it?s open.
Thank you
Dave

kklewin said:

Just had a co worker die in a Mustang II when the canopy opened in flight. It departed, tore off part of the tail, and the plane went in vertical. It also killed a 13 yr old son of another coworker. Pilot was a national aerobatic champion with 11,000 hours and part of the twin tigers air show team. I have a 6A and would never attempt to open or partially open a canopy in fight. But that?s just me.

Kurt

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I heard the same. My condolence.