Tight bridle = possible PC in tow?

[hackish 8]

I've been progressing through my packing course. My instructor has been in the sport for many years and has a lot of experience.

He has pointed out a few things to me about packing a chute - main thing I found surprising is that if you pack the bridle (on the bag side) under the closing flap so it's doesn't have any slack for the pin to loop around and come out of the closing loop then you can end up with a malfunction.

He demonstrated it to me and it does make sense. That is also why many bridles have velcro on themselves or on the top flap. It seems to me that someone not well instructed could easily miss something like this. Common problem or not? Is it just a low probability that it will cause a mal?

I guess I'll add that to my equipment checking routine.

Comments?

-Michael

[BIGUN 1,484]

You were instructed well.
Not a common problem - low probability.

Nobody has time to listen; because they're desperately chasing the need of being heard.

[councilman24 37]

This can and does happen. Many newer jumpers don't know what the velco is for, or to ensure there is slack. It's tough to get a bridle tight enough to cause a tow but it does happen. Many rigs don't have the reminder velcro, but I wish they did. And if you have a rig that has it keep it in good condition. This velcro wears out fairly quickly but is easily repaired.

One of the other common ways to cause a tow is to pull the pin and reclose the rig WITHOUT removing the PC from the pouch. It's very easy to misroute the bridle doing this. Saw it at our DZ this year.

I'm old for my age.
Terry Urban
D-8631
FAA DPRE

[hackish 8]

The guy teaching me to pack is Andre Lemaire and he's been in the sport for a lot of years. I trust his judgement and he's very thorough. The thing I find interesting is that such a big problem can be caused by such an easy to overlook problem. A number of others had "showed" me how to check the gear and how they packed their stuff but nobody had ever mentioned this.

I wonder if a modification such as sewing in a 1/2" piece of elastic material could make such a problem less likely. On just about every rig I've seen the velcro is falling apart.

-Michael

[ZigZagMarquis 9]

Quote

This can and does happen. Many newer jumpers don't know what the velco is for, or to ensure there is slack. It's tough to get a bridle tight enough to cause a tow but it does happen. Many rigs don't have the reminder velcro, but I wish they did. And if you have a rig that has it keep it in good condition. This velcro wears out fairly quickly but is easily repaired.

All very true.
An important thing in my mind to remember about the reminder Velcro is it is just (and only) that; to "remind" the packer that enough slack needs to me left on the bag side. As in, if its not there, its not a bad thing, other then its easier to "forget" or for someone who doesn't know, to miss. I've jumped a rig for years that had the "pile" portion of the reminder Velcro on the rig and the hook portion to the same on the PC bridle. When I R&R'ed the PC & bridle on that rig, the new PC & bridle had pile on the bridle, so, you'd "try" to mate pile to pile on the reminder Velcro. Obviously, it didn't stick, but still served as a measurement.

Quote

One of the other common ways to cause a tow is to pull the pin and reclose the rig WITHOUT removing the PC from the pouch. It's very easy to misroute the bridle doing this. Saw it at our DZ this year.

I've seen this scenario a couple of times too. Its happened both times when someone popped the pin on their main in the aircraft and instead of taking their rig off to re-pin it themselves, they just laid on their belly on the floor and had someone "fix" it for them. In either case, someone else either notied the person misrouting the bridle or said, "Hey, do a pin check" and then the misrouting was found.

[phoenixlpr 0]

Quote

He has pointed out a few things to me about packing a chute - main thing I found surprising is that if you pack the bridle (on the bag side) under the closing flap so it's doesn't have any slack for the pin to loop around and come out of the closing loop then you can end up with a malfunction.

This is the first time I hear about it. Pictures please!

[hackish 8]

I can take my cam to the DZ and try to get a pic of the situation he demonstrated. With the bridle tucked in very tightly I was able to life the entire rig up by the PC and the pin stayed in the closing loop.

-Michael

[phoenixlpr 0]

Which part was tight? Between the pin and the PC? How can you make it so tight? Mine just sliding out if you pull it. It is not even mentioned in out packing guide for students.

[ZigZagMarquis 9]

Quote

Which part was tight? Between the pin and the PC? How can you make it so tight? Mine just sliding out if you pull it. It is not even mentioned in out packing guide for students.

He's not talking about the part of the bridle between the pin and pilot chute being too tight... although, that part being misrouted can cause a pilot chute in tow... he's talking about the part of the bridle between the pin and the main parachute D-bag being too tight. If that part of the bridle is too tight, its rare, but it can also cause a pilot chute in tow because the pilot chute cannot pull the pin because there is not enough "slack" (if you will) in the "up side" of the bridle to move the pin out of the closing loop. This can happen but is very rare (IMO). I too have seen it demonstrated, but one has to work at it just to demo it (also IMO).

[councilman24 37]

Image 2167 is with the bridle tucked tightly under the side flap. IF the bridle is held tightly (I've seen a rig where the owner tucked it all the way under the bag) and the bridle is loaded before the pin is (IOW the PC pulls on the bridle under the flap first bypassing the pin) this could cause a PC in tow. Image 2171 is with an appropriate amount of slack in the bridle between the pin and the flap. The PC will pull on the pin first rather than the bridle. Image 2174 is a Vector II with the velcro on the bridle (bridle has black velcro) and rig. If the velcro is mated there is enough slack to pull the pin before loading the bridle.

I expect that this situation as a cause for a PC in tow is rarely confirmed. I'd expect that most of the time the reserve container opening would release enough tension on the main container to allow the PC to pull the pin. In fact I had a PC in tow in 1987. I was a rigger and had 600 plus jumps but it was an off season demo. The canopy in the dry winter air packed up pretty big and I remember the container being very tight. This was with an old wire pin and a pretty wimpy PC. The PC in tow cleared when I pulled the reserve. I actually hadn't considered it before but I might have made this mistake in that pack job. I was nervous about the demo site and was taking extra care with the pack job. I have attributed the PC in tow to the low airspeed hop and pop, the old PC, the somewhat rough wire pin and the generally tight pack job, but the bridle tightness might have played a part.

It IS very hard to get the bridle tight enough to not clear. The situation in the first paragraph might be one way. The bridle was long enough to reach around the bag to the side. I've also seen people tuck the extra bridle back under the top flap. With well maintained and/or ZP PC's I'd expect the bridle to clear most of the time. But my PC in tow might at low airspeed and an old F-111 PC represents the lowest force the PC would exert. The bridle location MIGHT have contributed.

I'm old for my age.
Terry Urban
D-8631
FAA DPRE

[phoenixlpr 0]

Thanks! That made it clear. I have different flaps configuration and bride routing, but its good to know.