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Re: Pterosaur size
----- Original Message -----
From: "don ohmes" <firstname.lastname@example.org>
Sent: Saturday, December 16, 2006 9:15 PM
Subject: Re: Pterosaur size
Let me ask a flight question. Let us arbitrarily assume that you are a
bird, or a winged whatever, and that from a height of 1000 feet in no-lift
conditions, you can glide a distance of 20,000 feet. Now, let's add 15%
your weight. Without flapping, how far can you glide in the same
conditions? Now, let's reduce your weight by 15%. How far?
--------- Ain't 20:1 high for a whatever? Just asking.
Not particularly. Diomedea exulans has a glide ratio of about 19-20:1. I
rounded off to 20 for convenience in multiplying.
Going from thin limits.
However, remember we agreed about that launch/flight/landing thing
being what counts? How the hell you get way up there at a 1000'? How do
your power requirements vary? I
don't start my marathon from the halfway point, although I have been
called a winged whatever.
Let's say that I dropped you out of an airplane. Or, alternatively, you got
up there the same way a wandering albatross gets up there.
When I talk about
flight or volancy in the context of biosystems, I mean the whole cycle. So
I need a more precise term
that isn't as hard to type as 'ecologically viable volancy' or
whatever. Flight cycle, maybe?
I repeat my question. Quantitatively, how does a +/- 15% weight change
impact gliding range?
and the Andes. Blackbirds that nest at 2500’ have lower
wingloads than sealevel nesters.
Not for any reason to do with flight -- it's actually to do with launch,
the variation between individuals or for one individual over time --
by more than the difference in density due to the 2500' change in
----------I don't understand what you mean, but I think I probably
Let's take Stonker for example. From memory, when he left Scotland he
weighed about 26-29 pounds. Upon arriving in Iceland 2-4 days later, he has
been weighed at weights on the order of 13 pounds. That's approximately a
50% weight change. On the other hand, the density ratio from sea level to
2500 feet is 0.929. That's a change of approximately 7.1%. Which is
-------------------- Damn. I was really hoping there was an answer to the
max observed launch altitude re cygnus. Think there is one,
Maybe, I dunno.
or do they launch right on up to .59 atm?
I doubt it. I don't think any of their usual haunts are at that altitude.