How to determine payload capacity?

[Base Glider]

I've been looking for a nice looking bird to put GPS and video on. The new RC B2 bomber with 2 ducted fan engines is coming out and I was looking for a way to determine it's payload carrying capability.

[Dick Huang]

Base Glider,
Down load Moto-Calc and add your play load mass to the auw to see if it will fly/climb.
Dick Huang:D

[Base Glider]

Thanks!

On a side note, is anyone else using Moto Calc?

Ever since I downloaded it I keep getting a pop up promo for pop up blocker as well as spam blocker.

[Dick Huang]

Base Glider,
I am using Moto-calc 7 and think it is a very good program. I was geeting lots of offers to buy Pop-Aid a pop up blocker. I paid about $20 for it. The program did not block all pop-ups so I don't recommend it mainly it caused crashes. I thought these pop-ups came from MSN and have nothing to do with Moto-calc. I hate pop-ups so am using a program called StopZilla now;it's better than pop-aid.

Dick Huang:)

[GordonTarling]

Base Glider - I would advise against use of fans on a model which has to carry such a payload. Fans work well at high speed and do not give enough thrust at low speed. What you need is wing area and pulling power. Flaps might also help. There are lots of airframes to choose from for GPS + video use, but you may like to look at the Telemaster or the Seniorita for a start. As Dick says, put your airframe into Motocalc and see what power system gives better climb rate with minimum current draw.

[Sail 'n Soar]

I'm also a satisfied MotoCalc user. I'm not getting the pop-up promos, though.

[Blue Sky]

What everyone else said.
Gordon is definately right about the ducted
fans.
For a plane that can truly make use of GPS
a 4-stroke gas motor would be the way to go.
If you're planning an electric plane then you
need a deeply geared brushless setup.
An electric sailplane also makes an efficient
camera ship but you'll need a big one to find
enough room for the extra electronics.
In the end electric powered flight comes down to efficiency. To get long flight times with an
electric plane you need lithium batteries.
This gets really expensive in a larger plane.
All this has been done before.
Here are a few links that might help.
Check out the links on the rccam group.
http://groups.msn.com/rccam/messageboard.msnw
MEC offers some nice brushless motor gearbox combinations.
http://www.modelelectronicscorp.com/
P-Calc on the web is useful for looking at
electric drivetrain options.
http://brantuas.com/ezcalc/dma.asp
Check this guy out!
http://www.cyber-flyer.com/
Good luck and have fun!
-Dave