Engines, Horsepower & Light Sport

James,

The Type Certificate Data Sheet (TCDS) is the certificate issued by the approving Authority. In the case if the Ercoupe 415C & CD the ACA was the approving Authority. The number A-718 is the identifying number for the ercoupe certification approved. The TDCS contains all the information on the aircraft ie Weight and Balance information control rigging required instruments, approved engines, propellers, AirSpeed limitations and everything it takes to meet the airworthiness standard of the original airplane. Each airframe, engine and propeller has a TCDS.

Take a few minutes and read your TCDS A-718. I think you will find it interesting.

Arlan
N3989H
415CD

Afraid I don't understand everything you just said, but appreciate the confirmation on the hp & engine type. A-718 and TCDS? Must be A&P talk. I am just a stupid sport pilot. who wants to learn more about his machine.

Per Wikipedia, the rules are:
Max. Gross Takeoff Weight: 1,320 lbs (600 kg) or 1,430 lbs for seaplanes (650 kg)
Max. Stall Speed: 51 mph / 45 knots CAS
Max. Speed in Level Flight (at sea level In the US Standard Atmosphere):138 mph / 120 knots CAS
Max. Seats: Two
Max. Engines / Motors: One (if powered)
Propeller: Fixed-pitch or ground adjustable
Cabin: Unpressurized
Fixed-pitch, semi-rigid, teetering, two-blade rotor system, if a gyroplane.
Landing Gear: Fixed (except for seaplanes and gliders).

I see no mention of HP, although I suppose a huge engine could affect max speed. Not an issue in an 415C since the max certificated airspeed is 120 mph

I own a 415C with the C-85 engine which I fly in the Light Sport category. Information (and mis-information) about what allows the Ercoupe 415 C (and CD) models to be flown as light sport aircraft abounds in the GA community. I know that anything you do to increase the gross weight beyond 1320 lbs takes it out of the LSA category. (Some have done that by converting their 'Coupes to "D" models.). My question relates simply to engine types and horsepower. I have heard that replacing the C-75 or C-85 with an O-200 Continental negates the LS rating. Some say "stroking" the C-85 with the O-200 crank (to give it 90 HP) also takes it out of light sport. Anyone out there have an official reading on any of this? I can't see how increase in horsepower would affect the LS rating as long as the airframe design is not changed to allow it to exceed the 120 knot LS limitation. With standard the wing design of the "Coupe, I really don't believe you could ever exceed 120 MPH unless you put a rocket motor on it!

I have no plans to do any of this to my plane, but I like to know as much about the subject as possible when talking to other pilots.

thanks,
James