AFAIK it is after any installation which
So after e.g. a repaint you have to do it.
Do you have to do it after a TKS installation, when the IM gives you the data:
I cannot imagine that reweighing the plane is necessary for (for instance) a 2.1 lb. addition, assuming good mass properties data. Is there an FAA reference for that requirement?
I need to reweigh my plane this year regardless, a friend has a good set of scales and my current W&B is clearly approximate – lots of changes over many years increase the margin of error.
Silvaire wrote:
I cannot imagine that reweighing the plane is necessary for (for instance) a 2.1 lb. addition, assuming good mass properties data. Is there an FAA reference for that requirement?
I don’t think there is. I’ve seen a number of W&B sheets where the mechanic does a calculation of how the W&B is changed without actually measuring it, and then creates a revised W&B default. Also, in skimming the FAA W&B handbook, there doesn’t seem to be a hard reference.
That being said, I would be hesitant to buy an older plane without a reasonably current W&B, because there seems to be a great deal of variability in how much useful load is available even between planes of the same make and model year. Obviously you could go through the plane and throw out redundant equipment (ADF, etc) and try to switch to a lighter paint job/interior/soundproofing or whatever, but without accurate W&B that is hard to know how much allowance should be made for that.
Usually a weighting is completed within half an hour, including all paperwork (just with the Lake it took a little longer, due to the distribution of masses) so I would not bother with long calculations.
In this case one would have to call in a company which does it and charges some £300-500. It also delays things because the aircraft is not airworthy until the W&B schedule has been done.
Adding the above mass and arm distance (18.4kg, 1.9m) to the existing W&B sheet should be dead easy. The TKS fluid is a separate item – like fuel, cargo, passengers…
Peter wrote:
AFAIK it is after any installation whichadds weight
the addition is over 2lb
the additional weight cannot be determined readily
So after e.g. a repaint you have to do it.
There are no FAR Regulations that state the above, so not sure where it came from.
Further, I cannot think of any instance where one could not computate the weight following the modification.
Peter wrote:
In this case one would have to call in a company which does it and charges some £300-500.
Of the advantages of Nregs…
Of the advantages of Nregs…
Could you explain? I do not understand.
The weight of a plane is not much affected by the weight of the number on the side. The process of weighing (IF weighing is required – that Q is why I started this thread from which I hoped others might benefit, which is what EuroGA is about) depends on whether you have the equipment to, ahem, do the weighing, or have to pay somebody to do it.
In “wealthy” Europe, if you have to pay somebody to get into a car and drive somewhere to do something, it’s gonna cost a few hundred €, so it is useful to know if this is mandatory.
I cannot think of any instance where one could not computate the weight following the modification.
I am sure a respray would be in that category (you are removing an unknown weight of paint, and adding some 10-20kg of new paint) even though that is not the case in my case right now.
Peter wrote:
I am sure a respray would be in that category (you are removing an unknown weight of paint, and adding some 10-20kg of new paint) .
The FAA regs do not mandate it and there is sufficient information on the weight of paint on various aircraft types and you can measure the thickness of the paint just for good measure.
I distinctly recall many statements over the years saying a weighing is mandatory after a respray, but that could be a European regulation.
And I can’t see how one could calculate it to better than +/- 5kg (10lb) or so, which is a fair bit considering the FAA considers a W&B change over 2lb to be significant enough.
