Van's Air Force
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Rv-3 airpeed certification
- Thread starter JimmyG
- Start date
Sonex effectively does this
This is effectively what Sonex does with the Jabiru 3300L engine installation. They claim the continuous horsepower rating is such that it is a 135 mph cruise at sea level, when it is capable of a 170 mph cruise at 8000'.
http://www.sonexaircraft.com/sportpilot/qualify.html
The light sport and sport pilot rules are here:
http://www.sportpilot.org/learn/final_rule_synopsis.html
So, I think the answer is "yes" but I wonder what the horsepower requirement for an RV-3 at sea level 135 mph is, and if that would pass the sniff test. The quoted performance at 55% power for a 125hp engine is 166mph, so you'd have a lot of ground to move it down to 135. I suppose you could simply use a highly under-pitched prop, so that at 2800 rpm you were throttle back to half or something. That thing would climb like a rocket.
This is effectively what Sonex does with the Jabiru 3300L engine installation. They claim the continuous horsepower rating is such that it is a 135 mph cruise at sea level, when it is capable of a 170 mph cruise at 8000'.
http://www.sonexaircraft.com/sportpilot/qualify.html
The light sport and sport pilot rules are here:
http://www.sportpilot.org/learn/final_rule_synopsis.html
So, I think the answer is "yes" but I wonder what the horsepower requirement for an RV-3 at sea level 135 mph is, and if that would pass the sniff test. The quoted performance at 55% power for a 125hp engine is 166mph, so you'd have a lot of ground to move it down to 135. I suppose you could simply use a highly under-pitched prop, so that at 2800 rpm you were throttle back to half or something. That thing would climb like a rocket.
RV3 LSA
My original plan for an RV3 was to use an 0200 engine I have. I just wanted the proven flight characteristics, not speed. Vans said the plane was designed for Lycoming . The mount, the cowl etc would be a problem and they had no information that would encourage the approach.
So I ended up with a 3B and 0320 engine and moved forward even though I have the experience and equipment to deal with the challenge. Regarding simply running the engine slower, installing a restrictor plate in the carb or whatever, consider this. I have not flown a -3, but the angle of attack might be undesirably high at 138 MPH with thrust limited to that speed.
I do plan to build an RV1 LSA. 0200 engine,RV3B wing and (undecided) tube and fabric fuse with flying wires in the tail for "nostalgia. I think the angle of attack issue could be addressed with higher incidence built in the wing attachment. How much incidence....good question.
My original plan for an RV3 was to use an 0200 engine I have. I just wanted the proven flight characteristics, not speed. Vans said the plane was designed for Lycoming . The mount, the cowl etc would be a problem and they had no information that would encourage the approach.
So I ended up with a 3B and 0320 engine and moved forward even though I have the experience and equipment to deal with the challenge. Regarding simply running the engine slower, installing a restrictor plate in the carb or whatever, consider this. I have not flown a -3, but the angle of attack might be undesirably high at 138 MPH with thrust limited to that speed.
I do plan to build an RV1 LSA. 0200 engine,RV3B wing and (undecided) tube and fabric fuse with flying wires in the tail for "nostalgia. I think the angle of attack issue could be addressed with higher incidence built in the wing attachment. How much incidence....good question.
Alex Caldwell
Member
Rv-3 airpeed certification
I think you'd be able to see over the nose just fine at 138mph. I don't think you'd need to change the angle of incidence of the wings to the fuselage if you've got enough power to cruise at that speed. You can see quite well over the nose in the RV-3, even in a 3-point landing pitch attitude, as long as you are positioned nice and high in the seat.
Alex Caldwell
RV-3A N1131T
Tulare, CA
I think you'd be able to see over the nose just fine at 138mph. I don't think you'd need to change the angle of incidence of the wings to the fuselage if you've got enough power to cruise at that speed. You can see quite well over the nose in the RV-3, even in a 3-point landing pitch attitude, as long as you are positioned nice and high in the seat.
Alex Caldwell
RV-3A N1131T
Tulare, CA
138 MPH
Thanks much for the feedback guys. Weight and balance will be the only unknown to predict / manage with a custom ( LSA ) RV3.
Thanks much for the feedback guys. Weight and balance will be the only unknown to predict / manage with a custom ( LSA ) RV3.
