Weight and balance questions

TangoWhiskey

Touchdown! Greaser!
Joined
Feb 23, 2005
Messages
14,210
Location
Midlothian, TX
Display Name

Display name:
3Green
1) Do you have to be an A&P to weigh an aircraft and issue a new weight and balance form for it? If so, both A and P, or just A (Airframe)? Since you're not making any repairs, it seems silly to require an A&P if it is indeed required, but...

2) Have you had your airplane re-weighed? If so, I'd like to know how much it cost to have done.

Thanks!
 
A reweighing is worth little unless it is accompanied with a new W&B and calcs of most fwd and aft moments. And the W&B is little more than worthless unless it has been signed and dated by an authorized person. I don't know any "A"s or any "P"s but I do know some A&Ps who can do the work.

It took $180 and a day to get set up and do the weighing on the Stinson a couple weeks ago. But I understand it may b as much as $300 for a single or light twin.
 
Troy Whistman said:
1) Do you have to be an A&P to weigh an aircraft and issue a new weight and balance form for it? If so, both A and P, or just A (Airframe)? Since you're not making any repairs, it seems silly to require an A&P if it is indeed required, but...

2) Have you had your airplane re-weighed? If so, I'd like to know how much it cost to have done.

Thanks!
I had my Bonanza reweighed a while ago after a major avionics installation. IIRC it cost about $250. The surprise was that it had gained about 100 pounds over the various recalculated weights in the logbooks when articles were removed and replaced over the years.
Stephen.
 
Richard said:
A reweighing is worth little unless it is accompanied with a new W&B and calcs of most fwd and aft moments. And the W&B is little more than worthless unless it has been signed and dated by an authorized person. I don't know any "A"s or any "P"s but I do know some A&Ps who can do the work.

It took $180 and a day to get set up and do the weighing on the Stinson a couple weeks ago. But I understand it may b as much as $300 for a single or light twin.

Thanks, Richard. I was not questioning the value of having it signed by an A&P, I was wondering if an A&P is the only person authorized by the FAA to create new W&B documents for an aircraft. In other words: if I had the equipment to weigh aircraft, but was not an A&P, could I create new W&B docs for my aircraft? Other aircraft?

I'd really like to find the CFR reference for this...
 
Troy Whistman said:
Thanks, Richard. I was not questioning the value of having it signed by an A&P, I was wondering if an A&P is the only person authorized by the FAA to create new W&B documents for an aircraft. In other words: if I had the equipment to weigh aircraft, but was not an A&P, could I create new W&B docs for my aircraft? Other aircraft?

I'd really like to fin

Troy, if I may, I think you are asking, "Am I, as owner, or as holder of at least a private pilot certificate, authorized to reweigh my own a/c and to make the appropriate logbook entry?"

After much editing and re-editing, here's the short answer.

Read CFR 43 and CFR 65. Unless you hold a mechanic's certificate or work under the direct supervision of a holder of such a cert; and unless you have the a/c mfg manual (or equal); you are not authorized to do the work.

The question of if a reweigh is maintenance or not is moot since you are not even allowed to perform the inspection.

However, if the purpose of the reweigh is to generate a current W&B it is maintence since the W&B is part of the airworthiness issue; if the purpose of the reweigh is just for grins (no mod, alteration, or repair) it then becomes an inspection. In either case, as an owner or as the pilot you cannot do the work (except under direct supervision) nor can you make the entry since being owner or pilot does not qualify you to do so.

EDIT: the only "A's I've run into are those just starting out. By the time they get to the point they can work without supervision they possess both "A" and "P". But to directly answer your question, I would think a guy with just the "A" would not be authorized since it is likely he does not yet hold the authorizing certificate.
 
Last edited:
Is it worth it? Yes, and as previously mentioned only an authorized person can sign it off, date and provide certificate number to make it a legal document in accordance with part 91.

Stache
 
Stache said:
Is it worth it? Yes, and as previously mentioned only an authorized person can sign it off, date and provide certificate number to make it a legal document in accordance with part 91.

Stache

You are likely to find that you have been overloading your aircraft when you load to what you thought was gross weight. For example, the two-ply tires your plane might have come with off the line have been replaced with heavier 6-ply tires. The battery with the extra cranking power weighs more. New leather seats by an interior shop? Did an A&P make an entry? Sometimes, but not always in the situations mentioned.
 
Richard said:
After much editing and re-editing, here's the short answer.

Read CFR 43 and CFR 65. Unless you hold a mechanic's certificate or work under the direct supervision of a holder of such a cert; and unless you have the a/c mfg manual (or equal); you are not authorized to do the work.

Thanks, Richard... I know that took you some time to research, and I appreciate it very much... I'll read those references!

Troy
 
Troy Whistman said:
Thanks, Richard... I know that took you some time to research, and I appreciate it very much... I'll read those references!

Troy

Well, your questions gave me a reason to read 43 again. What you saw wasn't so hard, what made it hard was figuring what to delete in order to not make a book of it. Anyway, everyone learns...
 
Gary Sortor said:
You are likely to find that you have been overloading your aircraft when you load to what you thought was gross weight. For example, the two-ply tires your plane might have come with off the line have been replaced with heavier 6-ply tires. The battery with the extra cranking power weighs more. New leather seats by an interior shop? Did an A&P make an entry? Sometimes, but not always in the situations mentioned.

It was those altogether missing and those, uh, 'partial' entries which compelled me to do the reweigh. I wanted to clean up the books on a 60 yr old a/c. I probably increased payload by 10 lbs just by vacuming the various loose nuts, washers, clips, screws, and bolts from the bilge.
 
Stache said:
Is it worth it? Yes, and as previously mentioned only an authorized person can sign it off, date and provide certificate number to make it a legal document in accordance with part 91.

Stache

Define "authorized person"

When the pilot does a weight and balance IAW the Cessna POH are they not an "authorized person"?

Computing data It is not a repair, and it's not an inspection, all it is, is a computation of data collected by placing the aircraft on scales.

The log book sign off is not a return to service, all it should say is "re-weighed aircraft and computed new empty weight of, _____ C/G located at __ inches aft of datum"

So I would conclude that any one that can compute weight and balance for safe for flight, can do this computation too.

read AC43,13-1B chapter 10.
 
Welcome back, Tom. A good vaca, I hope.


So, because it is not listed in Appendix A a reweighing is not preventative mx? And because it is not mx the holder of at least a private pilot cert can perform the work? Also, because it's not mx the PPL can perform the work without regard to 43.13?
 
NC19143 said:
Define "authorized person"

When the pilot does a weight and balance IAW the Cessna POH are they not an "authorized person"?

Computing data It is not a repair, and it's not an inspection, all it is, is a computation of data collected by placing the aircraft on scales.

The log book sign off is not a return to service, all it should say is "re-weighed aircraft and computed new empty weight of, _____ C/G located at __ inches aft of datum"

So I would conclude that any one that can compute weight and balance for safe for flight, can do this computation too.

read AC43,13-1B chapter 10.

Actually my reason for asking the question is that I've heard a LOT of homebuilders (and owners) say they have a hard time finding someone with the equipment to properly weigh their planes (i.e., a good set of calibrated digital scales).

I thought "hey, that might be a good aviation-related business I could get into on the side", that and dynamic prop balancing.

But I'm not an A&P... so I wanted to know if I needed to BE one in order to do this (or, have to hire one).

Now you know the REAL reason for the question. Doesn't it change the answer?
 
Troy Whistman said:
Actually my reason for asking the question is that I've heard a LOT of homebuilders (and owners) say they have a hard time finding someone with the equipment to properly weigh their planes (i.e., a good set of calibrated digital scales).

I thought "hey, that might be a good aviation-related business I could get into on the side", that and dynamic prop balancing.

But I'm not an A&P... so I wanted to know if I needed to BE one in order to do this (or, have to hire one).

Now you know the REAL reason for the question. Doesn't it change the answer?

Troy, form a company, find an A&P and assign him as RME.
 
I would like to point out experimental aircraft are not required to follow same rules as type certificated (T/C) FAR 43.1 excludes them. However T/C aircraft are a different story and A&P's are bound by FAR 65 for their limitations, weight and balance is part of their limitations. Owner/operator are bound by FAR 91 subpart E for maintenance and record entries. Subpart E states owner/operator are required to make sure maintenance persons make a record entry for work performed and give approval for return to service this includes weight and balance.

As pointed out Preventive Maintenance does not cover weight and balance. This is why it is the responsibility of the A&P during inspections to check the numbers to make sure they add up. If the numbers don't add up the mechanic has a duty to notify the owner to have the aircraft reweighted. The mechanic should write this up as a problem that needs to be fixed. This will then put the responsibility on the owner to have a person (A&P) with calibrated scales weight the aircraft. If you live in Northern California I know a person who will travel to your aircraft to weight it for about $200.00. He also teachs classes on weight and balance for free.

A great FAA book on this subject is FAA-H8083-1 Aircraft Weight and Balance Handbook. In the handbook it states mechanics must provide the pilot with current and accurate aircraft weight information and where its EWCG is located. The pilot in command has the responsibility to know the weight of the load, CG, maximum allowable gross weight, and CG limits of the aircraft.

I have a couple of copies of the handbook in the office if someone really needs one. I think it is very important that owners know how to perform weight and balance this way you can keep your mechanic honest. However to make your weight and balance a current and legal document it needs to be signed off by a A&P mechanic. Just remember the key to weight and balance is having the proper equipment (calibraded scales) FAR 43.13(a) and following the aircraft manufactures procedures. This can be done under the direct supervision of an A&P. If you as a pilot assist the mechanic your name needs to be in the record entry along with the the mechanics FAR 43.9.

Just one A&P/IA opinion.

Stache
 
Stache said:
I would like to point out experimental aircraft are not required to follow same rules as type certificated (T/C) FAR 43.1 excludes them. However T/C aircraft are a different story and A&P's are bound by FAR 65 for their limitations, weight and balance is part of their limitations. Owner/operator are bound by FAR 91 subpart E for maintenance and record entries. Subpart E states owner/operator are required to make sure maintenance persons make a record entry for work performed and give approval for return to service this includes weight and balance.

As pointed out Preventive Maintenance does not cover weight and balance. This is why it is the responsibility of the A&P during inspections to check the numbers to make sure they add up. If the numbers don't add up the mechanic has a duty to notify the owner to have the aircraft reweighted. The mechanic should write this up as a problem that needs to be fixed. This will then put the responsibility on the owner to have a person (A&P) with calibrated scales weight the aircraft. If you live in Northern California I know a person who will travel to your aircraft to weight it for about $200.00. He also teachs classes on weight and balance for free.

A great FAA book on this subject is FAA-H8083-1 Aircraft Weight and Balance Handbook. In the handbook it states mechanics must provide the pilot with current and accurate aircraft weight information and where its EWCG is located. The pilot in command has the responsibility to know the weight of the load, CG, maximum allowable gross weight, and CG limits of the aircraft.

I have a couple of copies of the handbook in the office if someone really needs one. I think it is very important that owners know how to perform weight and balance this way you can keep your mechanic honest. However to make your weight and balance a current and legal document it needs to be signed off by a A&P mechanic. Just remember the key to weight and balance is having the proper equipment (calibraded scales) FAR 43.13(a) and following the aircraft manufactures procedures. This can be done under the direct supervision of an A&P. If you as a pilot assist the mechanic your name needs to be in the record entry along with the the mechanics FAR 43.9.

Just one A&P/IA opinion.

Stache

Of course it is not preventive maintenance, it is not even maintenance, So why does it require a return to service?

Nothing on the aircraft is changed, or worked on. It was in an airworthy condition when it was weighed, and will remain airworthy, without a return to service signoff.

FAR part 65 does not say anything about weighting, or computing CG

§65.81 General privileges and limitations.

(a) A certificated mechanic may perform or supervise the maintenance, preventive maintenance or alteration of an aircraft or appliance, or a part thereof, for which he is rated (but excluding major repairs to, and major alterations of, propellers, and any repair to, or alteration of, instruments), and may perform additional duties in accordance with §§65.85, 65.87, and 65.95. However, he may not supervise the maintenance, preventive maintenance, or alteration of, or approve and return to service, any aircraft or appliance, or part thereof, for which he is rated unless he has satisfactorily performed the work concerned at an earlier date. If he has not so performed that work at an earlier date, he may show his ability to do it by performing it to the satisfaction of the Administrator or under the direct supervision of a certificated and appropriately rated mechanic, or a certificated repairman, who has had previous experience in the specific operation concerned.

(b) A certificated mechanic may not exercise the privileges of his certificate and rating unless he understands the current instructions of the manufacturer, and the maintenance manuals, for the specific operation concerned. [Doc. No. 1179, 27 FR 7973, Aug. 10, 1962, as amended by Amdt. 65-2, 29 FR 5451, Apr. 23, 1964; Amdt. 65-26, 45 FR 46737, July 10, 1980

65.85 Airframe rating; additional privileges.

(a) Except as provided in paragraph (b) of this section, a certificated mechanic with an airframe rating may approve and return to service an airframe, or any related part or appliance, after he has performed, supervised, or inspected its maintenance or alteration (excluding major repairs and major alterations). In addition, he may perform the 100-hour inspection required by part 91 of this chapter on an airframe, or any related part or appliance, and approve and return it to service.

(b) A certificated mechanic with an airframe rating can approve and return to service an airframe, or any related part or appliance, of an aircraft with a special airworthiness certificate in the light-sport category after performing and inspecting a major repair or major alteration for products that are not produced under an FAA approval provided the work was performed in accordance with instructions developed by the manufacturer or a person acceptable to the FAA. [Doc. No. 1179, 27 FR 7973, Aug. 10, 1962, as amended by Amdt. 65-10, 32 FR 5770, Apr. 11, 1967; Amdt. 65-45, 69 FR 44879, July 27, 2004]
 
I was checking and found the Weight and Balance Handbook for FREE as a down load if you need a copy at the following site:



http://av-info.faa.gov/data/traininghandbook/faa-s-8083-1.pdf


The requirement for the A&P to check the weight and balance is in FAR 65.81 during a 100-hour inspection and FAR 43.15(c) addition performance rules for inspections. Also FAR 43.16 Additional Limitation, which weight and balance falls in is a inspection..

In accordance with FAR 1, Definitions and Abbreviation states; Mainteance means inspection, overhaul, repair, preservation, and the replacement of parts, but excludes preventive maintenance. Weight and Balance fall under inspection and is considered maintennace, which would require a logbook entry.
Stache
 
Back
Top