[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: Hone and Benton 2007 (their second paper)
Michael Habib wrote:
Being in a tree actually makes launching quite easy, since the animal can
use a gravity-assisted >launch. Essentially, an arboreal pterosaur could
simply drop off the tree and then start flapping. It would hit flight
speed quite rapidly using gravity-assisted launch, so the animal need not
fall very far.
If I was a pterosaur, and I was dropping out of the tree as a means of
achieving flight speed - would I open my wings during this 'drop', or would
I keep them closed? I was thinking that by keeping the wings folded, I
would achieve flight speed sooner, since open wings would only create drag
during the brief descent. But if my wings are already open during the
'drop', then they are already positioned for the downstroke.
Arboreal birds use gravity assisted launches, as do cliff-dwellers like
tropicbirds. Arboreal birds do not require gravity assistance, while
tropicbirds (and frigatebirds) often do.
Can you expand on this a bit?
However, in both cases, the vertical descent prior to reaching cruising
speed is quite short. You can see it if you look for it, however. Like
arboreal birds, a tree-dwelling pterosaur would not require a gravity
assisted launch, but it saves energy if you happen to be at a high point
So in this situation too, would pterosaur wings be open or closed during the
vertical descent, prior to reaching cruising speed?
I hope that helps; definitely an excellent question.
It does; thanks for an excellent answer.
Make every IM count. Download Messenger and join the i?m Initiative now.
It?s free. http://im.live.com/messenger/im/home/?source=TAGHM_MAY07