Amphib Expertise required. PoF Question.
Gidday from Godzone,
Myself and a good friend are trying to sort a PoF question regarding forces on a PBY-5 Catalina @ S&L.
This post is also under Flying instructors but thought that someone in Canada must know this one.
Post reads -
Hi all,
I was asked about the forces for S&L on a flying boat. Easy enough; high thrustline + low drag = nose pitch down. To counter it you have an aft CofG and lift forward = nose pitch up. Same for a pure flying boat (Sunderland)
or for a tail-dragging amphibian (Widgeon), right?
Then came the question 'So how does that work on a Catalina?' The Catalina also has a high thrust line + low line of drag = nose pitch down. Went and had a look - tricylcle
gear means the CofG is forward of the main wheels , very close to where the line of lift must be. It defeats any reasoning the previous answer gave with regards to CofG position. The large wing is directly above the main wheels, I suspect CofG might be high and that the engines may be tilted slightly upwards.
So how does it work? I've tried to work it through, but I've run out of paper trying to solve it. The Kermode and the net haven't helped; they talk about the conventional method we already know. So, if you've got any ideas on this, any help you can give will be much appreciated.
(end question)
So if anyone out there can enlighten myself and my good friend, we'd be mighty appreciative.
Cheers
Sqwark2k