Changing gross weight with the FAA...

[DBVZ]

Is it possible to change the weight when you change the wings, for a non-builder owner? The different wings allow higher weights when building, but how do you do it later as a non-builder owner? And if the builder can set the max gross even higher than the kit MFG suggests for a particular wing, what can a non-builder owner do if he makes a "major modification" and submits the resulting new W/B to the FSDO?

[jtpitkin06]

Yes, you can increase the gross weight as an owner. It is considered to be a major modification just as changing the wings to a different airfoil or structure.


Refer to the operating limitations. It will tell you what to do in the event of major mods. Typically, you will notify the FAA, do new weight and balance forms, and re-enter the Phase 1 flight testing. You will be assigned a flight test area and need to fly off the hours. Probably 5 hours at max. You will make the appropriate logbook entries and then you are good to go.


Not really too complicated. But it is doable.


One additional note: If you increase weight above 1320 pounds, the aircraft may NEVER go back to LSA; even if you declare a future gross weight under 1320. The rule is clear. If an aircraft has EVER been operated outside of LSA then it may never be certified or operated as LSA.
Where some people get stung is putting on an in-flight adjustable prop. That automatically bumps you out of LSA forever, even if you later take it off. If it’s in the log… it’s history.


John Pitkin
Greenville, TX

[akflyer]

On what form do you submit the "gross weight" of your aircraft to the FAA?? Just curious cause there is nothing in the FAA files on several of the planes we fly localy that states anything about a "gross weight" ?

[DBVZ]

The one I am aware of is the W/B that the DAR signs off when you submit the program letter to go into flight testing. Not sure where that goes, but it is where the CG limits and gross weight are set, or so I was told. It does not show up on the AW cert or registration. My question was about if a "major modification" and a new flight test period of 5 hours (with a new W/B for the flight test) would work to change it. Seems like it does, even for a non-builder owner, if John Pitkin is right. Makes sense to me.

The next question is if the MFG plate on the tail gets changed too. Seems like it could be a ramp check problem, though you would have a more current W/B to show.

[akflyer]

If you get ramp checked, just have your latest W/B form and you should be good to go. When the FAA inspector came down and looked at my plane due to a "lost AW cert" (the original burned up in a house fire so said the original owner) he glanced at the paperwork I had put together for the total rebuild on the plane. He never looked at nor signed off on the W/B. I dont see any reason for them to do so. Then again, different FSDO's seem to do things MUCH differently and there is no real consistancy across the states. Maybe I just got real lucky to have a very nice guy come down and check my plane out. Too bad he retired a couple months after he handed me my pink slip.

[jdmcbean]

Yes, you can increase the gross weight as an owner. It is considered to be a major modification just as changing the wings to a different airfoil or structure.
Refer to the operating limitations. It will tell you what to do in the event of major mods. Typically, you will notify the FAA, do new weight and balance forms, and re-enter the Phase 1 flight testing. You will be assigned a flight test area and need to fly off the hours. Probably 5 hours at max. You will make the appropriate logbook entries and then you are good to go.
Not really too complicated. But it is doable.

Just a reminder that while the non-builder/owner can do the maintenance it does require an A&P to sign off the work. Also, you may be asked by the FSDO to substaniate the changes. The Data plate should not be changed.. It is actually against the regulations to remove the data plate.

While a ramp check will typically only look at the documents in the aircraft or on-hand and available they can request to see all the log books and other documents. Also, if there is an incident or accident you can be assured that all the documents will most likely be looked at either by insurance, FAA or NTSB.

[DBVZ]

I flew a Kitfox V where the builder did the same. The W/B the DAR saw was 1320, but nothing on the data plate. Most builders fill it in though, so as a subsequent owner you deal with what you have. 1320 W/B on a V that was designed for 1550 is one thing. I also saw an Avid IV with 1320 on the W/B the DAR saw, and 1320 on the data plate. HH wings that are usually considered 1150, though often increased to 1200 or 1250 with floats just because.

[MotReklaw]

EAA has an excellent kit for experimental home built aircraft that guides one through the process of registration. The instructions say to just enter the information required by the FAA, which does not include gross weight and the other info such as address, etc.
EAA will supply a data plate that has the information needed. I built two and didn't enter the gross weight on either. The DAR did ask me though what the gross weight was and looked at my W&B calculations.

(waiting for the weather to cool so I can get back to the hangar and get the wings hung on my SS7)......

[DBVZ]

I have been looking for Avid wing loading information. Help me understand the G-loading question. In looking for load ratings for the different wings used on the Avid Mk IV, I think I have this right:

Gross Weight G-load Wing Span

Speedwing: 1050 +6/-3 23' 11.5"

Heavy Hauler: 1150 +4.4/-2.2 29' 10.5"


My question is, if the Speedwing is +6/-3 at 1050, how does that change with increased weight? My simple calculation is 6 X 1050 = 6300 pounds loading. 6300/4.4 = 1432. So why not set the max gross at 1432? Or set it at 1320, and have a G-load of 4.77? If someone can direct me to authoritative load ratings for the other wings, I would appreciate it. Thanks.

[jtpitkin06]

Refer to AC 65-32.
Here's an excerpt that shows what to do for a major modification to an E-LSA. The E-AB procedure is pretty much the same.

As pointed out, if you are not the builder, you can do the work but you'll need an A&P or the original repairman certificate holder to sign it off. You can do the flight testing yourself.


"Major Alterations. Because the aircraft is issued an ELSA certificate, a non-certificated
person may perform additional maintenance, preventive maintenance, or alterations on the
aircraft. If a major alteration, as defined by § 1.1, is performed, such as changing the engine to
another model that increases the original engine horsepower by 10 percent or more, a
maintenance record entry and a new FAA Form 8130-6, Application for Airworthiness
Certificate, must be made and sent to FAA, Aircraft Registration Branch, AFS-750. A new FAA
Form 8130-6 is required because the aircraft has been modified and is no longer the same aircraft
as identified on the original FAA Form 8130-6 in the aircraft’s file. A designated airworthiness
representative (DAR) or FAA aviation safety inspector (ASI) will review the change(s) and issue
new operating limitations for the aircraft. The new operating limitations may require the aircraft
to be put in a flight test area for a certain number of hours until the new alteration has been flight
tested and the aircraft is proven to be safe to operate within its design envelope. When the
flight-testing is complete, the test pilot should sign the aircraft off as safe-to-fly in accordance
with its operating limitations. (See Appendix 1, Figure 2.)"