4 fatal - crash nw of Waterloo ON Aug 24 2012

[PilotDAR]

The weight and C of G position will make a different to stall and spin handling, the aircraft could handle very differently. However, in all cases it will handle compliantly, which includes the measure "must not require unusual pilot skill, attention or strength. So, yes, pilots should be aware of the differences, because they are surely there, but different absolutely does not mean not recoverable. Also in the standard: It must be impossible to create an unrecoverable spin with any use of the controls - that means it WILL come out, if you recover it properly. Even in the normal category, with back seat occupants, it will recover a spin, but, as it is not spin approved in that category & configuration, it probably Will require unusual pilot skill and attention. That is one of the dividing lines for spin approval.

In any case, you have to be demonstrating pretty poor pilot skills to not be able to stall and spin a 172, and not recover it with a few thousand feet to play with. It might not be a pleasant ride, but it is doable.

In my opinion, a 172 is a great training aircraft, and even better and more safe, if the back seat is removed. 'Prevents temptation.....

[Colonel Sanders]

People just don't understand (or care) how
an aft C of G can drastically change the
handling characteristics of an aircraft.

In flight training, students only fly the 172
with a forward C of G, where it is docile, and
they become contemptuous towards it.

You treat an airplane with contempt, it can
(and will) kill you.


Even fewer people understand that two aircraft
with the same W&B (same weight, same C of G)
can handle completely differently if they are
loaded with a different PMI.

They think that if the weight and C of G is ok,
life will be peachy. No.

Remember, the airplane can't read.

[FenderManDan]

Even fewer people understand that two aircraft
with the same W&B (same weight, same C of G)
can handle completely differently if they are
loaded with a different PMI.

They think that if the weight and C of G is ok,
life will be peachy. No.

Remember, the airplane can't read.

I am aware the academic differences of the different CofG config. I also had a chance to fly 172 at MTOW and felt some of the handling differences. Most notably the climb out and slowing down in the circuit were feeling different.

"PMI", can you please explain in more details what do you mean?

[trampbike]

Polar moment of inertia

CoG only takes into account the longitudinal distribution of the weight.
You could have 2 identical CoG, but in one aircraft, the cabin is lightly loaded and the wings full of fuel, and vice versa. The 2 aircraft will behave differently, expecially in a spin.

EDIT: I just saw that CS started a thread on this subject in flight training.

[flyinthebug]

TSB report is out.

http://tsb.gc.ca/eng/rapports-reports/a ... 2O0138.asp

No surprises here. The only comment I have is that despite all the experts involved in the investigation of this crash, and the months of pain staking & detailed investigation, even they couldn't determine whether the spin was intentional or not.

My most sincere condolences remain extended to the family and friends of those lost on this tragic accident.

Fly safe all.