Ask the DAR

Questions about operating limitations when changing engines and adding avionics for IFR.


Question: I purchased an E/A-B a while ago and put a new engine on it that is very near the same weight as the one it was originally registered with. It now has a four-cycle, although the FAA registration information indicates a two-cycle. I also added all-new wiring and plumbing, as well as a new propeller.

My operating limitations say, “If the major change includes installing a different engine (reciprocating to turbine) or a change of a fixed-pitch from or to a controllable propeller, the aircraft owner must fill out a revised Form 8130-6 to update the aircraft’s file in the FAA Aircraft Registration Branch.”

I’m not sure what documentation I am required to submit (if any) to the FAA to be legal for these changes. I also want the FAA registration to reflect the correct engine information.

Answer: The first thing that jumps out at me is your quote from the operating limitations, specifically the part where it says “installing a different engine.” I hope you simply mistyped this, and your op lims actually state “installing a different type of engine.” If this is the case, you do not need to submit a new 8130-6 at this time.

After receiving the 8050-64 (number change authorization), within 10 days you will submit a new 8130-6 to the FSDO/DAR to request a new airworthiness certificate. Be sure that the new engine information is correct on this form. However, don’t be surprised if the two-stroke to four-stroke change doesn’t make it to the online listing of the registration. The FAA Aircraft Registry is not well known for keeping these details up to date.

Airshow coverage sponsor:

Question: My RV-7 has been flying since 2014. I built it and hold the repairman’s certificate. Last year I installed a new EFIS system with a Garmin certified GPS unit, an updated transponder for ADS-B Out, a com radio, and a standby attitude indicator. The airplane now meets or exceeds the equipment requirements for VFR night and IFR flight as established in FAR 91.205.

According to my operating limitations letter, the aircraft is to be operated VFR or as mentioned in paragraph 8, “After completion of phase I flight testing, unless appropriately equipped for night and/or instrument flight in accordance with 14 CFR 91.205, this aircraft is to be operated under VFR day only.”

So now that the aircraft is appropriately equipped, do I need any update to my operating limitations, or does meeting paragraph 8 legally allow me to fly IFR? I’m guessing I am good to go as long as I also meet all the equipment inspection criteria for IFR flight. I am also current for IFR flight.

Of course, I don’t want to guess, so I figured it would be a good idea to get a correct answer.

Answer: Yes, you are good to go. Your operating limitations do not need updating. If your aircraft is equipped and maintained in accordance with part 91.205, it is legal to be flown at night and/or under instrument flight rules.

Please send your questions for DAR Asberry to with “Ask the DAR” in the subject line.

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.


Please enter your comment!
Please enter your name here

This site uses Akismet to reduce spam. Learn how your comment data is processed.