Gross Weight VS Max Takeoff Weight

[Mnflyer]

Its a dumb question I should have known better sorry

[84KF]

GB,
I'll make this brief
A difference is.....
The definition of "maximum takeoff weight" includes the weight of "Full fuel, including a minimum of the half-hour fuel reserve required for day visual flight rules in § 91.151(a)(1)."

As stated in the Final Rule...,
"Some commenters stated that lacking
a definition of maximum takeoff weight,
aircraft with fairly high performance
characteristics could meet the definition
of light-sport aircraft by limiting the
approved weight and payload of the
airplane. The FAA considers this a valid
concern and has provided some
additional constraints on the weight as
detailed below
The maximum weight of
a light-sport aircraft is the sum of:
(1) Aircraft empty weight;
(2) Weight of the passenger for each
seat installed;
(3) Baggage allowance for each
passenger; and
(4) Full fuel, including a minimum of
the half-hour fuel reserve required for
day visual flight rules in § 91.151(a)(1)."
Federal Register / Vol. 69, No. 143 / Tuesday, July 27, 2004 / Rules and Regulations 44793

The typical usage of the term "gross weight" makes no distinction When discussing weight and balance, it is implied to mean the total weight of the aircraft regardless of the load condition.
2 occupants + full fuel and baggage = "gross weight"
4 occupants + 1/4 tanks, no baggage = "gross weight"
"Gross weight" must not exceed "maximum weight", the "official" term used in a certificated aircraft's Type Certificate Data Sheet

There is no FAA definition for the term "gross weight"..., and the term is not used in Final Rule.

I mean no offence to any one despite how I may come off in my posts, and I welcome all comments. This is how we learn. As a former Part 147 maintenance school instructor I tend to be (just a bit) head strong in my "lectures". Sorry.
GB, don't hesitate here one bit in any quest for new information....or to correct me if I am mistaken. (I was once...back in the 1900's.

...additional edit...
Post script:
Example:
My a\c empty weight is .... 760 lbs
My weight is .............. 180 lbs
Passenger weight is..... 180 lbs
Full fuel weight (as required) 156 lbs
Baggage weight....... 15 lbs
---------------------------------------------
Total (calculated, possibly not actual, due to less actual fuel load) weight at takeoff..... 1291 lbs....which is less than 1320 lbs...., which is the "maximum takeoff weight" allowed under sport pilot privileges.

[84KF]

In accordance with PART 45--IDENTIFICATION AND REGISTRATION MARKING
you are required to show the following.....

§ 45.13 Identification data.
(a) The identification required by §45.11 (a) and (b) shall include the following information:

(1) Builder's name.

(2) Model designation.

(3) Builder's serial number.

(4) Type certificate number, if any.

(5) Production certificate number, if any.

http://ecfr.gpoaccess.gov/cgi/t/text....363.2&idno=14

Note that items number 4 and 5 would not apply to amateur-built aircraft, so items 1 through 3 are the only info required on an amateur-built aircraft data plate.

But...., what does that "max weight" number have to do with how the aircraft is actually be operated under sport pilot privileges?? Nothing. Is the aircraft supposed to just break if ever flown at say.. 1321 lbs?
The DOT\FAA rule does not "penalize" just because the aircraft is well designed and efficient.
The thing is, it's irrelevant... think of (LSA) MTOW is an operating limitation required under sport pilot privileges, not a number, such as found on a TCDS, which is the only place you will find the weight limits on certificated aircraft.

Remember... we are talking Experimental Amateur-Built here.... Not Light-Sport Category aircraft (ELSA & SLSA) which have certification requirement issues of their own.

[RandyL]

Steve, thanks for all the info. You are of course correct on all points and way more up on the actual regs than the rest of us.

From a practical point of view though most of us are building kits designed by a kit manufacturer who has indeed established a "Gross Weight" (and CG range) which it has been engineered to and which is important to observe in use. Also, isn't it true that although "gross weight" is indeed not on the Airworthiness Certificate, Registration, or in the Operating Limitations, it is reflected in the W&B documentation which is required by your FAA Inspector or DAR for certification and, IIRC, is required to be carried in the aircraft? For those reasons I think it's easy to understand the confusion on all this.

[84KF]

The "kit manufacturer" is not the "manufacturer" of the actual aircraft in the eyes of the FAA... the builder is.

The "kit manufacturer" has no control what so ever on the quality of the workmanship, individual fabrication techniques, and the durability of many (extra) materials and hardware utilized during construction. The finished product is not the fault of the "kit manufacturer", rather it is is an "experimental" aircraft... manufactured by an "amateur" builder. Who knows how it will actually perform, and at what point it will structurally fail.

The construction designs, and operating limits implied by the "kit manufacturer" are not FAA approved, and the builder is not under any legal obligation to conform to the "kit manufactures" instruction or recommendations.

We are continuing to confuse the issue with a fixation on the words, or term, "gross weight" when, in reality, they\it have nothing to do with sport pilot rules... as said before, the term is not included, or implied in the Final Rule.

Respectfully,

[RandyL]

The "kit manufacturer" is not the "manufacturer" of the actual aircraft in the eyes of the FAA... the builder is.

Good points, and right you are again.

Respectfully,

[84KF]

My Kitfox 5 received it's airworthiness certificate in 1998.... and as I stated in a previous post...."It is not "licensed" or "certified" to any "gross weight".
There is nothing in any paper work on file with the FAA that mentions, or implies a "gross weight".
There is nothing in my Operating Limitations that states a "gross weight". (I will forward all the paperwork to anyone interested who requests it.)
There is no" gross weight" listed on the data plate

Review the application and registration process and show me exactly where one "certifies" the aircraft to any specific weight. http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/0ca2845e2aafffbb86256dbf00640cb2/$FILE/AC20-27F.pdf
Show where in APPENDIX 5. SAMPLE AERONAUTICAL CENTER FORM 8050-1,
AIRCRAFT REGISTRATION APPLICATION , APPENDIX 6. SAMPLE FAA FORM 8130-6, APPLICATION FOR AIRWORTHINESS
CERTIFICATE (AMATEUR-BUILT) (FACE SIDE) or APPENDIX 6. SAMPLE FAA FORM 8130-6, APPLICATION FOR AIRWORTHINESS
CERTIFICATE (AMATEUR-BUILT) (REVERSE SIDE) where one submits the "magic numbers"

Randy L writes...
"...isn't it true that although "gross weight" is indeed not on the Airworthiness Certificate, Registration, or in the Operating Limitations, it is reflected in the W&B documentation which is required by your FAA Inspector or DAR for certification?"

It may be in some (not mine) , but is it required? No....

In accordance with APPENDIX 13. SAMPLE PROGRAM LETTER TO ACCOMPANY
APPLICATION FOR AIRWORTHINESS CERTIFICATE one should answer "yes" to the question "I have weighed the aircraft to determine that the most forward and aft center of
gravity positions are within established limits. The weight and balance report is
available at the aircraft, and a copy is submitted with this application
....and the words "gross weight" or "maximum weight" do not appear in AC No.: 20-27F, CERTIFICATION AND OPERATION OF AMATEUR-BUILT AIRCRAFT , the FAA publication I have been referencing in this post.

It is then the responsibility of the PIC to ensure that the most foward and most rearward limits are not exceeded, what ever the loading situation is at the time of flight.
I have to ask this... how can one be expected to "determine" what the "maximum weight" capability, structural or otherwise, of the aircraft is at that point in time.... it has not even been test flown yet?

[RandyL]

It is then the responsibility of the PIC to ensure that the most foward and most rearward limits are not exceeded, what ever the loading situation is at the time of flight.
I have to ask this... how can one be expected to "determine" what the "maximum weight" capability, structural or otherwise, of the aircraft is at that point in time.... it has not even been test flown yet?

Steve,

I've been immersed over in the RV world (5,700 flying planes) for the last eleven years and must say you bring the facts to light in a way I've never heard before. Thanks for the thoughtful and correct interpretation of the regs. Instead of just blindly following common interpretation you are taking the time to understand them and interpret accordingly. Of course that's part of what you do as an A&P with I.A., but its good to have some informed dialog on these issues. With this whole new set of regs we have to operate in (LSA) it's good to have some sharp minds reading and interpreting.

Thanks,

[jonbakerok]

I've been looking for a Kitfox for almost a year and I've ignored the 5's because I thought they didn't qualify as LSA. So I'm going to need some clarification. Are we saying that since the W&B info isn't sent to the FAA when you register your experimental, you can just change the gross anytime you want?

When I built my RV6, my DAR made sure I had the weight and balance written in the log and I had to have a W&B sheet with example loadings in the airplane. He wanted three things on the dataplate -- name, date, and gross weight. Are we saying that because the FAA never got a copy of the W&B, I could have turned it into an LSA by adding an entry to the log and changing the dataplate and W&B sheet?

Hey, nothing I sent to the FAA said it would cruise at 192 MPH, either.

Jon Baker
RV6A sold, RV4 in-progress
Looking for a Kitfox

[RandyL]

Hi Jon,

I'm an RV guy going Kitfox as well. I know for a fact that all the paperwork you submit to your DAR or FAA Inspector remains in a file at the FSDO they work out of and this includes the W&B documentation, equipment list, and everything else you submitted with it. W&B docs, and the builders understanding of them, are important and no DAR/inspector I've ever met would ever grant an AW Cert without them.

Some of us, me included, were using the term "gross weight", which I believe we get from the kit manufacturers, in place of MTOW (maximum takeoff weight). Steve (84KF) is correct in pointing out that the term "gross weight" is not the correct term, and that it actually doesn't appear in your AW Cert, Registration, or Operating Limitations. Again, they are on file at the FSDO however and ARE a factor in determining LSA compliance.

I think the real issue however is what qualfies or enables a particular aircraft to operate as an LSA so that the pilot can exercise Sport Pilot priveledges. As we all know certain older certified aircraft (Cubs, Champs, etc.) qualify as their various parameters fit within the LSA parameters. I would think that any new E-AB aircraft (not S-LSA or E-LSA) who's speed and weight parameters fit within the LSA regs would also qualify. Then of course any S-LSA or E-LSA aircraft would also qualify since it must meet the ASTM concensus standards. Regarding E-AB aircraft meeting the ASTM standards: I believe that's a gray area where there is some wiggle room. I for one am NOT clear on that particular area. I do know that the current Kitfox meets all parameters if not equipped with an in-flight adjustable prop which is why I will not equip mine with one.