Did you know that in general, Americans now eat about 20% more food than they did in the early '70s :ooh: ..

Well, they are not getting taller and they exercise less so it has to be stored someplace - maybe it's time for Robinson to manufacture a R-22 XXXL version with trible-piston powered engines and still only two seats :p ..

madman you are not wrong in your direction.

One of the problems that all aircraft manufacturers have to deal with now is the increased average weight (or should I say mass in this pc time...) of the occupants of an aircraft. Unfortunately few of them are addressing the problem.

The biggest problem is with the older aircraft, mainly US built light aircraft of the 1960's to 1980's. Recently I had an application to learn to fly from a gentleman who admitted to 130kg, but looked larger. This was for a light helicopter, where thankfully the manufacturer had put a maximum seat mass into the flight manual. So it was easy to decline.

But wait for the law suits. "Discrimination" they will cry, when all of us in the industry know that there is a psychological reason why obese people should not fly aeroplanes.

Aviation requires self discipline, which includes the discipline of health. People who chose to get obese are unlikely to have the strength of character to learn the subject and stick to it. If you cannot stick to a regular diet, it is unlikely that you can handle the regimentation of civil aviation.

[back in the foxhole awaiting incoming]

Nice logic moosp. But it falls down if you use your eyes. How come there are so many overweight pilots around? How is it that a fair proportion of the fat asses trying to fit into R22s are instructors, not students? Where's self-discipline when half the pilots I know live on junk food and beer? Like I said, nice idea, but nothing to do with reality.

I resemble that remark, Whirly !

Robinsons and fat asses
 

So, with fat instructor and student in the seats, plus students coat , camcorder, and lunch. In the event of the instructor not reacting quickly enough after student has put in a unexpected foreward push of the stick, would it be reasonable to assume that a blade chop is more prevalent when two biggies are at the controls.

bugdevheli:

IIRC, blades chopping the tail boom off is related more closely to RRPM, not necessarily low G, and not AUM.

If an instructor doesn't react quickly enough if the stude pushes, then low G will be the first problem to contend with. It's only if the subsequent reactions are wrong that mast bumping will become an issue.

As part of certification, testing of critical flight conditions is done at max AUW - check the H/V curve as an example, and in cases where it's relevant a delay time is built in. If testing in this area was required for certification, then theoretically the situation should be recoverable relatively easily. However I think the only testing done in low-G was after certification to determine the most effective recovery. In short, I'm not sure your theory is a reasonable assumption, but my thinking isn't clear enough to be able to write it down.

Help, anyone ?

Strange that nobody has mentioned Centre of Gravity. I recently looked at 4 flying school R22s where two pilots, each of whose weight was within the seat limit, and with a fuel load to put the aircraft even comfortably below the MAUW limit, were nevertheless outside the forward CG limit.
Have you checked your R22 CG calculations?
Incidentally, these aircraft had not all been weighed by the same organsiation at the same time, so there is some possibility that this state of affairs is prevalent.
Makes you think. Flying out of CG could really make your eyes water.

Robinsons and fat asses
 

Nr Fairy. Take your point about the low main rotor rpm, but given the ammount of movement either by flexing on the geabox mounting rubbers together with bending of the main rotor shaft and its outer tube, plus crushing of the plastic stops on the mast under mast bumping conditions. It would be informative to know if any statistics are available regarding blade to boom contact incidents and occupants weights.

bugdev:

And what is the relative movement of those items listed compared to a 12 / 14 foot long blade ? I'd suggest that it is the blades which are going to flex far enough rather than all the other items combined, no matter what the weight (or should that be mass) in the cabin.

Idle stop - you get the impression that CG calculations are generally ignorred by the training fraternity.
I have to agree with you.

From my experience having mentioned CG to several newly fledged PPL's I know that they are very hazy, ( very foggy) about the need to carry out meticulous CG calculations. Many dont know how to do CG calculations as they have not been required to do them during their training before each flight.

Simply said. weight AND CG must be within limits.

Fat arses keep out

Robinsons and fat asses
 

Nr Fairy. Having (FOR EXPERIMENTAL PURPOSES) carried out some static fexion tests on a well known helicopters main rotor shaft, its quite impressive how far it moves before any permanent deformation takes place. I will do the sums as to the relative tip to boom distance when I have a clear head. Just as an aside, I have tried similar flex tests on the rear cross tube. The ammount of force and movement required to straighten a bowed tube when it is off the machine, makes you realize how well the fragile looking rear side frames are designed and made,in order to be capable of dissipating these loads during a heavy landing. Be nice to know what the steel and alloy specs are for these components (anybody know?).

So from this, can I gather that anybody around the 100Kg plus weight is a "fat arse"?
I would like to see this theory bandied around some of the rugby clubs around town, where some weigh a little more than that and are far from being a fat arse. Methinks that this may result in the perpetrator of such a theory may just get to log some flight time without the benefit of rotors.....

I am new to this game, but from what I have read on the matter,
some of the issues here such as mast bumping could happen to anybody irrespective of their weight as it occurs in a roll under 0 G conditions created by something like an abrupt pushover, or is it only fat arses that are capable of such flying manoevers. Not everybody is skinny, pilots included (neither am I ) ....and I sincerely hope that as I progress I do not have one of those that criticize as has been noted on this forum as an instructor. Despite having a Telecoms diploma, a HR Training & Development Diploma, a Financial Management Diploma as well as a multitude of Technical Competency Certificates I am now doubting that due to the size of my gut, I will not be able to master the theory of flying.....sod it, I was really looking forward to it! Maybe balloning will be better!!!!!:p

In my experience, all our student were weighed, as were we instructors, and a complete W&B was conducted regularly during flight training. We had some heavier machines that were impractical for a heavy student and instructor, a couple with odd CofG locations that required higher than normal minimum fuels to remain within limits, and other restrictions. A student who couldn't provide the correct details in a preflight brief didn't fly.

With regard to heavier pilots, not everyone fits in the little machines and if you still want to do the training then paying for a larger machine is sometimes the only legal or practical alternative. Breaking the rules isn't.