t-max97

My Feedback: (9)

I wasn't sure where to post this but I'm thinking about making a "trap door" on the bottom of one of my trainers while It's all apart because I'm recovering it, How would you go about this? I was thinking of dropping one of those toy soldiers with the little parachute out of it.

JohnBuckner

My Feedback: (1)

For that you don,t need a trap door. Just an extra servo mounted inside with two rod ends going out the side of the fuselage There should be a block of wood on the inside glued to the ply where the rods exit this adds a bit of strength and enough bering surface when the rods are retracted. When the rods are extended #64 rubber bands are hooked over the rods and down around the fuselage bottom and what ever the pay load is that is to be dropped.

John

rolliedog12

My Feedback: (3)

I built a bombay inside my Telemaster.  There was plenty room inside the plane I built a  bombay box out of light weight balsa.  Placed two doors running the lenght of the bottom, using plasic dubro hinges.  I then glues two small servos at each end with a Y harness.  Then glued the entire system inside the fuselage.
I use to have an exterior bombay on an LT 40 that I would velcro it to the bottom of the plane between the tricycle gear.  Both systems work, but having the bombay inside the plane really cuts down on drag.  I have dropped numerous items, the best being a 60 foot party streamer and then attempt to cut it with the plane.  The most important thing is to place it so that it doesnt disrupt the center of gravity.

t-max97

My Feedback: (9)

Thanks for the idea, I may do that but I didn't really want it on the outside of the plane. I was thinking a small door on the bottom of the fuse towards the end, when I hit the switch one end would lower.

t-max97

My Feedback: (9)

Sounds cool thanks for the idea.

rolliedog12

My Feedback: (3)

Trust me you will have fun with a bombay, there are so many things you can drop. My Telemaster will hold about 8 small parachutes. I have dropped candy to kids, flour, homemade bombs......And other things that I wont list!!

52larry52

My Feedback: (1)

t-max97, rolliedog 12 is right on with his advice. Placing your drop box as close to "over the C/G" as possible is important to having a good flying airplane with the box loaded and then with the box empty after the drop is made. I also second the motion to put it inside the fuselage rather than an external box added to the bottom of the fuselage. I have a candy drop plane with such an add on (but removable) external drop box, mounted over the C/G but it turns a very sweet easy flying trainer into a plane that I can't wait to get back on the ground after a drop. The plane flys poorly with the drop box on it, dosen't matter if the box is full or empty. Over the C/G and inside the fuselage is the way to go. PS, I bet I know what trainer your rebuilding !!!!! have fun.

foodstick

I built my last Sig Senior JUST so I could have a bomb drop. So much fun at the end of the day when the field is quiet and the winds are calm...

I will tell you the one best decision you can make on your bomb drop. Somehow build a hatch so you can load it thru the top of the wing or the side of the fuse. WAY easier than stuffing the payload in from the bottom !

t-max97

My Feedback: (9)

It's the one the guy at perry gave me, I'm pretty sure it's a sig but I don't know what model "it's old", thanks for the advice I'll try to figure something out. Are you going to taildraggers tomorrow?

52larry52

My Feedback: (1)

t-max97, OK, I am wrong on what plane you are working on. I didn't know about the freebee from Perry. I figured you were rebuilding the one that got crashed at Taildraggers last year ( a Tower Trainer 40 I think). No, I won't be at Taildraggers tomorrow, as I have a family activity planed (grandkids). Say "hola" to all for me.

t-max97

My Feedback: (9)

I already fixed and have soloed that one, BTW I had my radio tested "the one he said lost connection and caused the crash" and it tested fine, I figured.

hugger-4641

My Feedback: (6)

I made an external drop module from a Crystal Light container, but you could easily do something similar with the bottom of a large Cub. I cut two doors lengthways in the bottom, it looks just like real bomb bay doors when it opens. I built one that only had one large door that swung down, but this proved to be a lot of drag when the door was open. Using two doors allowed a lower profile and I can even land with the doors open if the servo were to fail. The doors are activated by two pushrods expoxied to the hinge line of the doors, and the pushrods actually are the hinge.These extend thru both ends of the container, with the threaded end of the pushrod extending out the back and used to hold the cap on. This way I can remove the cap and reload the container without having to turn the plane over.