300lb (130kg) pilot

On Saturday, March 7, 2015 at 5:33:56 PM UTC+13, wrote:
Hello everybody, I'm a instrument rated private pilot with 120 hours TT, all single engine piston A/C.

I've been meaning to get a glider rating for a long time, mainly because I want to learn soaring and possibly do some light aerobatics on the cheap.

However I've been steered away several times due to the lack of options of gliders that would accomodate my size, height and weight.
I'm 300lbs, 6'3", tall, fat, big, with VERY wide shoulders.

I'm 5'11" and about 280 - 285 lb. I'm a (junior) instructor at my club, taking members of the public for their first lesson, and students close to or just after solo standard but not yet cross country rated for soaring flights.

As with any aircraft, a glider's published maximum limits and performance numbers don't stand alone, but form an interrelated web.

Many light aircraft have two or more sets of figures published (for example normal or utility or aerobatic category) with different maximum weights, maximum G loadings, C of G position, takeoff roll, climb rate etc.

Gliders don't usually have that on paper, but in reality similar tradeoffs apply.

The first thing is that 110 kg (242 lb) seat loading limit. That is calculated so that seat belts and mounts will survive a 40 G crash. If you're not planning to crash, or if you'll keep the crashes down to 20 or 30 G then you can ignore that. Some owners may decide they don't want to ignore it ("if you crash our insurance may be declined"), others are more relaxed. Technically, if it was not a contributing factor to *causing* the crash (and it won't be, as such), then there should be no grounds to decline a claim. I've found that Australian clubs are sticklers for this (and thus I haven't been able to fly there) while NZ clubs are relaxed about it.

The second thing is all up weight and weight of the non-flying parts. These are structural strength things. Our DG1000 two-seat trainers are rated for 7 G aerobatics. If you're 5% or 10% (20 or 40 kg) over the maximum weight of the non-flying parts then you're going to be ok if you de-rate the maximum G. Personally, I have no desire to do anything that involves more than 3 G, or maybe 4 very briefly. In soaring glider flying you don't go over 2, other than from gusts. It's also a good idea to de-rate the Vne.

The third thing is Center of Gravity. That's the important one. Going too far rearwards (light pilots) is a killer. Don't do that. Going too far forwards may be slightly bad for performance, as you tend to constantly need more up elevator than normal, however it is not unsafe, as long as you are prepared to use (very slightly) higher takeoff and landing speeds. If you have trouble getting it to rotate and lift off on takeoff then abort. When in free flight, find the minimum possible flying speed (you may not be able to get it to actually stall), and use that as the "stall speed" for approach speed planning ("stall" speed plus 10 knots plus half the wind speed).

In a two seater, the back seat is often much more roomy, and always has a smaller effect on the C of G. Unless I'm flying with someone in the front seat who is themselves over 90 kg (200 lb), I have the DG1000 at pretty much the ideal C of G position (with the tail weight compartment full).


In a small piston plane, overloading is dangerous primarily because of the longer takeoff run (I think T/O distance proportional to weight to the power of 2.5?) and the reduced climb rate. Actually breaking the things in mid-air is not usually the problem.

With a glider launched by the typical powerful Pawnee or winch that is simply not going to be an issue.

Interesting comments from Bruce. Just be aware that any time you exceed the numbers in the aircraft manual, YOU are now a test pilot and risk taker.
Providing rides to the general (unknowing) public, and anything happens causing injury, an unlatched canopy, hard landing, rope break into the trees or rocks, and you have just introduced yourself and your club to a world of liability issues. Same goes with students, who are relying on the experience and knowledge of their instructors.

I agree with you logic on flying to reduced G loads or Vne, but I do not agree with the practice.

This will not happen in my club. I am at 210# and know the max weight of any student or passenger I can take in any glider I fly.
We live in a very sue happy environment now. Why ask for a problem you cannot defend.
BillT

Discussed before at https://groups.google.com/forum/#!to...ng/fRDFby79mzA