George,
To change it back to be a C, you just change the elevator restriction back to the C limits and file the form 337 with the FAA and ask for a new airworthiness certificate. But, why would you? Once the aircraft has received its airworthiness certificate as a 415-D (or later) model, even if you change it back to its original model it still may NEVER BY FLOWN WITH A SPORT PILOT ACTING AS PILOT IN COMMAND. (Sorry to shout, but I wanted all lurkers to not miss those words lest they get into problems.) If the pilot is not a Sport Pilot, then it's better for the plane to be a D, allowing the 1400 lb. gross weight. If the pilot is a Sport Pilot or a higher rated pilot flying under the privileges of Sport Pilot due to letting the FAA medical expire, the regulation says you must be flying a "Light Sport Aircraft." The official definition in the regulations for a "Light Sport Aircraft" says: * * * * * Light-sport aircraft means an aircraft, other than a helicopter or powered-lift that, since its original certification, has continued to meet the following: (1) A maximum takeoff weight of not more than-- (i) 660 pounds (300 kilograms) for lighter-than-air aircraft; (ii) 1,320 pounds (600 kilograms) for aircraft not intended for operation on water; or (iii) 1,430 pounds (650 kilograms) for an aircraft intended for operation on water. (2) A maximum airspeed in level flight with maximum continuous power (VH) of not more than 120 knots CAS under standard atmospheric conditions at sea level. (3) A maximum never-exceed speed (VNE) of not more than 120 knots CAS for a glider. (4) A maximum stalling speed or minimum steady flight speed without the use of lift-enhancing devices (VS1) of not more than 45 knots CAS at the aircraft's maximum certificated takeoff weight and most critical center of gravity. (5) A maximum seating capacity of no more than two persons, including the pilot. (6) A single, reciprocating engine, if powered. (7) A fixed or ground-adjustable propeller if a powered aircraft other than a powered glider. (8) A fixed or autofeathering propeller system if a powered glider. (9) A fixed-pitch, semi-rigid, teetering, two-blade rotor system, if a gyroplane. (10) A nonpressurized cabin, if equipped with a cabin. (11) Fixed landing gear, except for an aircraft intended for operation on water or a glider. (12) Fixed or repositionable landing gear, or a hull, for an aircraft intended for operation on water. (13) Fixed or retractable landing gear for a glider. * * * * * You'll note the words, " since its original certification" in the lead-in paragraph of the reg. So, while it's not hard to change a Coupe back to be a C, no one in their right mind would do so if there is documentation findable by the FAA or insurance company showing it was ever changed to be a higher model. It seems that an error in REGISTRATION isn't enough to spoil it as a higher model. A model D or higher Airworthiness Certificate is absolute. A form 337 on file with the FAA that can be found in the aircraft's documents (get the document CD from the FAA) seems to be a permanent Sport Pilot disbarment. Does that answer your question well enough? Ed Ed Burkhead http://edburkhead.com East Peoria, Illinois ed -at- edburkhead???.com (change -at- to @ and remove "???")
