Re: helicopter not equal rocket

[John Denker <jsd@MONMOUTH.COM>]

At 04:27 PM 8/18/99 +0100, Ludwik Kowalski wrote:
> It seems to me that introductory physcs courses can benefit from
> teaching about helicopters before airplanes. At that level the approach
> is much easier, conceptually. At a more advanced level, when fluid
> dynamics, and its advanced mathematics, are involved the "airplanes
> first" approach may be easier or more desirable. I have no experience
> with this but the arguments presented make sense.

Go ahead and try it if you like, but I still recommend against it.

1) Possibly helpful suggestion: Try rockets.  Rockets are in certain ways
simpler than airplanes.  Teaching rockets before airplanes makes sense.

2) I say again, helicopters are very different from rockets.

3) A helicopter is an example of what is called a _rotary wing aircraft_.
I don't understand why anyone would think for an instant that that rotary
wing motion is simpler than straight-line wing motion .... unless you make
such a crude approximation that the helicopter looks like a rocket.

Think about the order in which things were invented:  rocket, airplane,
helicopter.  That should be some sort of hint as to the relative complexity.

4) I keep daring people to explain translational lift using the
helicopter-as-rocket model.  Still no takers.