Plane is a Telemaster 40. Dimensions of box are undecided as of yet, but does the idea seem sound like I have shown in the picture?

Might work. Go to the BTE, Bruce Tharpe Engineering web site and see the design he has for the Giant Flyin' King. It is similar.

Rich

I think as soon as you open the door, the airflow is going to rip it right off.

Or, it will act as an air scoop and keep the candy from falling out.

Mike,
Check the graphic again. I think the door will be swinging down with the opening away from airflow, in which case, the airflow would tend to hold the door closed.
Dennis-

After a careful reevaluation of the door mechanism, I have decided to attach the servo directly to the door and make it swing to the side rather than the front or back. This will allow the door to cut through the airstream more efficiently and reduce the workload of the servo as it opens and closes. Also by closing the door before landing, I reduce the risk of damaging it or the servo.

P.S. Minn, add a little right rudder, your drifting. LOL

Ive often wondered if you couldn't place the servo in front of the box and have the door SLIDE open.
Use a long control arm with a pushrod attached to the door. The door could slide on 2 little "L" shaped rails and then be opened and closed at will.
If you wanted ALOT of travel for the door, a little linkage inventiveness could do that.
Or I wonder about placing a control horn on the hatch and have the servo pull it down off of hinges. (like flaps)

Why bother with the chute??

just put the door on the bottom of the candy box and be done with it......

candy would then come out on nice level flight


seems risky to need to do a bunch of aerobatics over a large group of kids to get the candy to fall out....

exeter, the only maneuver that would be necessary would be to raise the nose over the drop point. If I have it figured right, it will produce a more accurate drop by allowing the candy to fall in a more vertical path than horizontal. Correct me if my thinking is wrong on this, but if the plane is going more vertical than horizontal then the payload dropped will also?

No dennis, look again...

The direction of travel is to the left, which meane the airflow will be from left to right.

In any case, Here are two suggestions. The first is the complicated, but cool way, and the second is the simple way

1 - Bombay style doors (Or a single door) that open sideways to the airstream.

2 - A single hinged "Trap Door" that will open when released by a pushrod that acts as a latch, and remains open throughout the rest of the flight

Mike...Mike Mike Mike....Your drifting again...LOL Dennis was correct is his observation that the direction of travel in my drawing would make the airflow keep the door closed or impede the drop. Much like your #2 drawing, only reverse the direction of travel. Your #1 drawing is very interesting to me, in that it looks more like the real thing. Could you elaborate on the technical details of creating functional "bombay"style doors? And as always Minn, Thanks for being an excellent source of information and a great resource to the RC and RCU communities.[8D]

OHHHHHHHHHHHH!!!!!!!

NOW I see it! DUH! It looked to me like the "Release Latch" was a control horn.

Not much to elaborate on, You can hinge the doors any number of ways. The biggest thing is to add some plywood "Control Horns" (The black things in the picture with the pushrods attached) at 45 degree angles so the pushrods can open AND close them.

The 45 degree angle makes sense. What puzzles me, and I guess it will make more sense once I start putting things together, is where the servo should be placed to keep the linkages out of the way of the payload.

I can think of two things:

First, you could have the doors longer than the payload box, so that the 45 degree control horns are outside the box (No pun intended)

Or have the horns in the same place, but run them to the doors with torque rods (A little more difficult)

Here is another configuration I have been pondering. It uses two boxes mounted on each side of the fuse under the wing. This should keep the weight at or near the CG. Wooden arms (red) stretch through slots in the fuse sides to each box. Two servos, one for each box, actuate the doors which fall as shown (blue). I am only using a 4 channel radio on this plane so I have an idea for releasing the doors which will remain open through landing. Both doors will attach via rods to the rudder. Full deflection of the rudder in either direction releases the door on that side. A quick left/right throw of the rudder stick and both doors open in near succession. Or I could make two passes since the Telemaster would most likely fly easily with an offest in lateral balance so close to the fuse. Another advantage is to have two different payloads. Perhaps one of candy, and one of small toy parachutes.

You forgot the pic

Added pic above.

I'm not crazy about that idea. If these doors are going to remain open for the duration, they should open front to back, not side to side.

In a Front to back configuration, the airstream will keep them open. they may flutter a bit, but no biggie.

In a side to side configuration, each slight change in direction will cause a full deflection of the door in the opposite direction, so the door will be slapping back and forth throughout the flight.

My concern about opening them as you suggest is that they act as air brakes or flaps. Wouldn't that add major drag? By opening them to the outer sides, they may cause minor disturbance in the yaw axis, but that's decreased by the give/sway of the door that would swing inward during the turn. If they are light enough, the Telemaster most likely won't even know they exist. As soon as the LHS opens back up I will get the supplies to make the boxes. I want to start a pictoral follow-up on this thread.

In my configuration, as long as the hings is flexible enough to allow the door to fold 180 degrees back, the Tele won't even flinch with it open

A pair of small magnets could be added to the fuselage and door to maintain the open state of mikes blow back design.

Not a bad idea!

the box is gonna cause major drag. but as for the door thingy, you could go to your local magic shop and get flash paper...flash paper is somthing that burns rather cold and ultra fast, and I mean super ultra fast. it wont even scorch the plane. or the kids, use an electric trigger of sime form to make a spark (glos plug to a servo activated switch for the power source? maybe) but in any case if you layer this so that it will hold the weight well when triggerd you wont have to worry about doors. just use a cardstock type paper for a flash plate so the candy wraping isnt harmed. it should fit AMA guidlines I think. no projectiles and I would hardly call a 1/30 of a second flash a fire. would you?

Hi,

I have been dropping candy for years. Here are some pictures of my Candy Man. If you would like more information, let me know. I fly inverted and open with a servo. The air load opens the top. Monokote for the hinge. (Yes, monokote, about three layers) It does not rip off in flight and trails in the open posistion with no movement. I have it on the top so I can land, reload and take off in a very short time. It works great. (Of course..........there were several earlier "versions" that didn't work!)

Scott