Ask the DAR

Registration and Repairman Certificates.


Question: I am considering the purchase of an Experimental/Amateur-Built aircraft and have questions. Specifically:

The aircraft was originally built and registered in Canada. It was later re-registered in the U.S., and then had an engine type change. What paperwork should exist for that engine change? Currently the FAA registration web site says engine type unknown.

I want to change the avionics. What does the FAA require to make a panel change?

I plan to place the aircraft on floats. What does the FAA require to make this change?

Answer: I assume that when you say engine type, you are talking about changing a particular type of reciprocating engine to another type of reciprocating engine. This is technically not a type change. A type change would be from a reciprocating engine to a turbine. If there was an actual type change, a new 8130-6 (airworthiness application) should be sent to the FAA registry in Oklahoma City to update its records. If the change was simply to a different reciprocating engine, that can be done with a logbook entry, a new weight and balance, and a new Phase I flight-test period. Don’t be concerned about the engine type listed on the FAA registration web site; many registrations have bad data in this field.

A change in avionics can also be done with a logbook entry. If it involves a notable change to the weight and balance, or if there is any interface with the aircraft control system, such as an autopilot hook up, then the aircraft must be placed back into Phase I flight testing for a minimum of 5 hours. Be aware that if any portion of the static system has been opened, the transponder certification becomes invalid and must be redone.

Basically the same situation applies to float installation. Logbook entry, new weight and balance, and then back into Phase I for at least 5 hours.

As always, when dealing with Experimental or Light Sport Aircraft, read your operating limitations carefully. There should be a paragraph relating to major changes that will guide you through the process. Operating limitations vary depending on when they were issued. You will most likely be required to notify the local FSDO (Flight Standards District Office) for approval of the proposed flight-test area.

Question: There was a builder/owner who discovered an exhaust crack on his biplane 2.5 hours from home. While repairing it on the ramp, a guy started asking questions. After a few minutes, he identified himself as an FAA inspector and proceeded to inspect all paperwork. He asked the owner for his Repairmans Certificate and was told it was back at the hangar. The inspector told him to stop working until he could produce it or he would be cited for illegal maintenance. If you purchase an Experimental and are not the builder, I thought you could work on the plane, and just need an A&P to sign the condition inspection. Whats the rule?

Answer: The FAA inspector is completely wrong in this case. The aircraft builder/owner can perform all maintenance and even major modifications to an Experimental/Amateur-Built aircraft. The sole purpose of the Repairman Certificate (part 65.104) is to perform and sign off the condition inspection. Only the person holding the Repairman Certificate for that aircraft or an A&P mechanic (inspection authorization not required) may do so.

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Mel Asberry
Mel Asberry is an experienced Designated Airworthiness Representative specializing in Experimental/Amateur-Built aircraft. He and his wife, Ann, have built seven amateur-built airplanes including two ultralight types, a Moni Motorglider, a Dragonfly Mk2, two RV-6s and a Zenair CH 601HDS. They are currently building a scratch-built biplane.


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