Springbok Flyer

Hi guys,

Starting to install my first drogue chute and I have absolutely no experience or even personal sighting of one being used. My initial questions are:
- How to secure it to the jet, given that there is a chute carrier/box involved?
- How far behind the jet should the chute be when deployed?
- I don't have a spare channel to make some sort of chute release. So any suggestions as to how best to handle the deployed chute on the ground after the landing and rollout?
- What is the best method of loading the chute in the box for best operation?

Thank you for your help.

Jan

mullerr

This link may help you, it should help you with your questions and more, good luck.
​​​​​​​Skymaster CF104 Airframe and Scale Goodies - RCCanada - Canada Radio Controlled Hobby Forum

mullerr

Sorry wrong link
​​​​​​​Skymaster 1/5 F104 Starfighter / Behotec220

rhklenke

My Feedback: (24)

Lots of guys will tell you that you need a release to drop the chute after landing or if it accidentially deploys in flight.

I have had two airplanes with a chute and neither of them had a release. The chute never deployed in flight and after landing, I just dragged it back. Generally, unless there was a lot of wind, the exhaust keeps the chute inflated (mostly) and it stays off the ground during taxi back.

Also, if you land at a jet meet and drop your chute in the middle of the active runway, you'll won't make friends with the guys waiting to land while you retrieve it...

Bob

Springbok Flyer

Bob,

Could you please tell me how far behind the jet I should have the chute when it has deployed? Also, any special way of folding and loading the chute into the box for efficient deployment?

Thanks,

Jan

ozief16

My Feedback: (13)

Jan,

What I've done to secure the chute in the plane is to run a Sullivan cable through inner nyrod (the yellow stuff) from my servo to the back of the plane. In the back I have about a 1/2" gap between the end of that nyrod and another 3/4" piece of the nyrod. The servo pushes the cable (which I silver solder for strength in the area where it will span the gap between the two pieces of nyrod). Simply make a loop in the end of the chute cable and hold that in the middle of the gap in the nyrod, have the servo push the cable across the open space between the nyrod and into the far side. It's very strong and releases the chute no problem

donyou need a release? Maybe maybe not. If the chute accidental deploys in flight it will probably just rip free. You don't want to leave the chute in the plane in between flying sessions in my mind so a way to take it off the plane would be nice at the end of the day

In terms of deploying the chute...if you're out of channels you can get the auto chute from dan gill (details for Scale). It takes inputs from throttle flaps and brakes as well as a wheel speed sensor and will deploy the chute automatically when all values are met (i.e. Flaps at full, throttle at idle, brakes on c percent and the wheels start spinning). Unit works great and doesn't take a channel

How far behind the plane? Look at google images of your plane and see what it really did. In general it's a lot farther back than I think it should be. Usually about one fuselage length as a rough hack

how to fold. Look up the Auto Chute instructions on the details for Scale website. He has folding instructions on there. When I do it that way it always works

mr_matt

My Feedback: (10)

I have a system wherein with the flaps up, the parachute is "released" such that if it were to deploy it would just fall away ( I heard a horror story about a cook F-4 chute deploying in flight, it left an impression on me). This is a separate servo connected to the flap channel.

With the flaps down, the chute is now locked on. After touchdown, if you want to jettison the chute, just raise the flaps and the turbine exhaust blast will blow it off. If you want to leave the chute on, just taxi with the flaps down.

I tried to come up with a break away chute but it always broke on landing

DelGatoGrande

My Feedback: (23)

http://www.rcuniverse.com/forum/rc-j...22how-%22.html



my 2c

.

Springbok Flyer

Thanks guys,

I am installing one in a SM F-104 and the attachment and release with the chute box hinging down underneath the fuse is not allowing for the common attachment and releasing methods. However, the distance of the chute behind the jet and the folding and loading of it seem generic.

Jan

ColinW

Don't know how easy it would be to engineer, but a lot of full size have a system where the chute is unlocked till selected i.e. if it streams when it hasn't been selected it will come straight off. When selected the chute is locked onto the aircraft. This needs a lock that only comes into use when the chute steam is streamed.

Springbok Flyer

I have had a look, but cannot find the instructions on 'how to fold - please can you post a link?

Jan

DelGatoGrande

My Feedback: (23)

did u ever played with an estes rocket? If not search for there instructions .They will show you how it folds

CARS II

My Feedback: (7)

Watch this video.

causeitflies

Exactly what I was thinking

Springbok Flyer

Thanks George, I will see if I can find it.

Jan

JSF-TC

My Feedback: (2)

Jan,

I scratch built a drag chute for my DerJet Hunter. I 3D printed a chute release mechanism that operates both the doors and the chute release with a single servo.

Basically, the servo moves a piece of piano wire that protrudes aft and engages a hook on one of the 2 overlapping spring loaded doors. This one door holds the second door closed. The servo is on a 3-position switch - Closed/ Deploy/ Jettison. From closed, on selecting Deploy, the piano wire is pulled forward enough to release the spring loaded doors. The chute is retained by a loop around the piano wire inside the pocket in the 3D printed frame. On selecting Jettison, the wire is pulled forward further, allowing the loop to slip off the wire.

Sorry, don't have a good photo of the actual install, but it works well.

I scaled the cute dimensions from a photo of the full-scale. It ended up matching the 16" D4S chute - I just asked for a 5 segment chute rather than the 4-segment standard offering. Don't hold your breath for delivery - took almost 1 year to get.......

It looks and works great and it is extremely powerful - it will stop my Hunter in about 350ft with a slight headwind and no wheel braking. Chute and wheel brakes will get it stopped in about 200ft.

I did have one inadvertent deploy at around 15ft AGL just prior to touchdown - pilot error in moving my finger to the switch, and Oops!!!. Nearly totally destroyed the model as it stopped in mid-air and pivoted nose down and smashed into the runway. 4 months of reconstruction and the plane is flying great again. I've now fitted a locking 3-position switch to my Tx to protect against another inadvertent deployment.

I think it is worth the effort to have a working chute.


Regards,

Paul