I have a friend who needs to drop a small package (of course following all FAA regulations about taking proper care to not cause damage to people or property) from about 500ft. He's well practiced with aim because he likes to drop pumpkins after halloween. But now he needs to drop something, could be a case of ice cream bars, without damaging the contents. Any suggestions? He's thought about copious amounts of bubble wrap and a long fabric tail, or a small parachute, or individually attaching toy soldier parachutes to each sandwich, etc.

A tent fly from any standard dome tent makes a fairly good parachute. Attach shroud lines to the tie-down loops to suspend the payload.

Freeeze em hard an wrap em in a sleeping bag...

That's a good idea, I hadn't thought of that.

Test it with a dummy payload that you don't care about

I bunch of Boy Scouts are doing a 50 miler and want me to drop them supplies. Did not think I could do it and than this post came up. do not think a 182 is suited for the job but what do you think. Never dropped anything but banna peals and an occational bag of puke over Berkley.

Just kidding about Berkley, Just dreaming

Tim

This is a similar situation. My friend is thinking that ice cream bars really can't be damaged too much, he just needs a way to slow them down so they don't separate on landing and feed the wildlife instead of the scout life.

Love dropping zip lock pee bags over lakes that people are fishing on. Wonder if I've ever hit somebody?

Bubble Wrap!

you could try science...

You need to figure out the terminal velocity of the package (http://en.wikipedia.org/wiki/Terminal_velocity), which requires figuring out the drag coefficient (http://en.wikipedia.org/wiki/Drag_coefficient).

Once you have the terminal velocity then you figure out how suddenly your package will stop when it hits the ground - it will be a short distance but it won't be zero (package crumpling, grass or brush, sand or snow, etc). That will be enough to figure out the decelleration forces that your package and its contents will experience when they hit the ground.

Next you need to figure out what happens to ice cream under those decelleration forces - i.e. deformation and/or fracture under dynamic loading caused by deceleration. The basic dynamic loading equations are easy (http://en.wikipedia.org/wiki/Strength_of_materials) but getting the required data for the ice cream might be tricky. You might need to do some experimentation with a centrifuge, which might get messy...

Or you might just want to try lots and lots of bubble wrap and duct tape...

Nice. I may be down the first of the week.

Tim

I wrote out a post with all the math, but it got lost on the interweb. Anyway, it turns out that the terminal velocity of 3 packages of Fat Boy Ice Cream Sandwiches taped together and surrounded in duct tape is about 68mph. My test idea is to create such a package, drive the car at 68mph and toss the ice-cream bomb out the window at the side of hill. Now I have something to do tonight!

With twenty fire seasons behind me, I have a few hints.
1. You fly and have someone else drop.
2. If you are flying a Cessna, a package of any size will only go out the window if the stop is removed.
3. If the package is padded and light for it's volume, it may float and hit the tail. If you put something on it to slow its descent, it may drape over the tail.
4. If the package is too large to go out of the window, the door will have to come off. You won't be able to get the door open against the slipstream to throw a package of any size out. If you want to supply the scouts, that will entail larger and heavier amounts and the packages will probab;y be desroyed in a free fall. We dropped bundles of sleeping bags by free fall, everything else had chutes.
5. Don't use chutes unless you or someone else really knows what is gong on.
6. If what you are dropping is valuable or needed badly, practice. Hitting the ground in the right spot is hard.
7. Because our pilot population is ageing and having prostate issues, how many zip lock bags of pee do you figure are dropped each year?

robertc wrote:...If you want to supply the scouts...

What he meant to say was "...If your friend wants to supply the scouts..."

Long long ago in a land far far away, many folks stuck way out in the hinterland in the winter time, got their mail from an air-drop from the local air taxi pilot or game warden. Had to put a long streamer on it so it could be retrieved after it buried itself in the deep snow.

A helicopter survey operation got jet-a in 55 gal barrels air-dropped into the water then retrieved with a boat, rolled up on the shore then wobble pumped in the the aircraft. Water is more forgiving than a pile of rocks.

Hi Chip nice to see u still here

Alan, Just have your friend land and give them the Ice cream bars. Scouts would love that. Three packages of Fat Boys could do some serious damage at speed to a Scouts head and you know they will try to catch it. Or if you had a parachute wrapped around your friends tail, they might get to watch your "friend" crash. Neither one would be good for anyone. Think "Darwin Awards" here.

Here's my idea, comments welcome;

-freeze them hard to reduce impact damage.
-wrap them in bubble wrap & a web of rope to make an attach point.
-attach a long streamer to slow the velocity. Wrap it so it won't stream until released.
-fasten it to the lower gear leg with a quick release knot or a short dowel as a pin. Run the rope into the window as a trigger line.

Would that get it far enough below the tail to prevent a strike?

There's a Talkeetna/ Denali story slowly coming back to me. I think I actually saw this in a written account. Maybe someone else here can corroborate or debunk it. As I heard it:

One of the glacier operators- Geeting, maybe- had a special bomb hatch in the belly specifically for airdrops, since they are commonly used up here. Because it required a second person to man the hatch, this pilot would bring a friend and instruct them when to pitch things out. (When the target disappears beneath the cowling).

Flying into base camp one time, there was a generous cargo of treats, like beer and junk food and even a frozen halibut as a gag.

Getting low and lining up for the first pass, the pilot and bombardier had to resort to yelling at one another over the engine and noise from the open hatch. From the left seat, the bombardier was heard to ask "What should I throw first?", to which the pilot shouted in reply "Halibut!"

Circling back for the second pass, the pilot was shocked to see utter pandemonium on the ground below. Flattened tents, people running and waving, etc, etc... "What the heck did you throw?", the pilot shouted over his shoulder. From behind, his friend shouted "Half of it, same as you told me!"

One case of beer reportedly landed right between two climbers, resting inside their tent.

Good times...

A friend of mine who grew up in rural Alaska told a story of a 20lb block of Hamburger hitting a tree one winter. It seems the family pet is good for finding frozen hamburger chunks in deep snow.