Re: Needs Scales for W&B?
Posted: Tue Jun 19, 2018 8:24 pm
As a side note, I think it is required to weigh and figure the weght and balance for an airplane that is used for 135 charter service every 5 years.
The discussion forum for Sport Pilots and Light Sport Aircraft
drseti wrote:I guess I'll have to take my LSA off of 135 service.
MrMorden wrote:If you know the weights and arms of your changes, you can do a recalculated W&B without weighing the airplane again. Since that is an acceptable method to the FAA, I'd always take that option over weighing.
When they get re-weighed, airplanes often mysteriously gain weight, whether from tools &supplies forgotten in the airplane, an "optimistic" original factory weight, or just accumulated dust and grime.
If you calculate the weight, you will be sure you are only adding the weight of your changes. If you get the scales out and they show a bunch of added weight, you are stuck with that number. I would not expose myself to that possibility if I could avoid it.
Scooper wrote:Andy, the gross weight of the '63 172D is 2300 lbs, not 2450 lbs, but you're right about 15 pounds not being that big a deal. The problem is that with all the changes I made, I didn't know if it was 15 lbs or 50 lbs, and trying to calculate it would have been more complicated and less accurate than simply weighing it.
Here are the before and after photos, but there's lots of stuff you can't see (autopilot computer and servos, heavier "Real Gaskets" pushrod tubes on the O-300, etc.).
MrMorden wrote:My only point is that usually when the history of the airplane is well known a calculated W&B is prefectly safe.