October 22, 1797: From Balloon to Parachute

That is quite a fascinating tale, Immediately after the dreadful events of 9/11, I was asked what I would have done in the circumstances. Probably panic like most, was my honest answer, "could I have cobbled a parachute from available resources like curtains etc" I was asked. "Probably not", but then I pondered that at least with care a longish rope could be obtained from such material, cut into strips and tied together in knots. An Office might well contain sticky tape in abundance and also plastic dustbin liners. probably hundreds of them. If one scrunched up newspaper, not too tight, and just filled as many bags as possible. Then attached three bags at regular intervals to the makeshift rope. Let us say throw out a line of ten to twenty 'bunches of three' paper filled bags, from a window, It might be possible that a lightweight person could reach the ground safely, if they followed after and trusted to providence. I would, I suspect, probably be far too heavy. Any CR4 volunteers? I doubt it, but a crash-dummy might prove/disprove the hypothesis. Spiders are known to fly off on threads of silk. to the other side of the world at times. A thread parachute, perhaps with a multiplicity of miniature parachutes, could be well worth investigating. Or has it been done? if so, what were the results?

I recently I saw a TV program where someone is patenting (or has patented) a "skyscraper escape parachute", to allow people to leave a high building when due to fire or other problems, the normal methods are not available...... Brought on of course because of 9-11.....The rest of the details I have forgotten, sorry.

I can only wish those entrepeneurs luck, though if one has foresight, a parachute would be needed for each and every person. Far better a rope that reached the ground. Mountaineering Suppliers could cater for this need. The advantage, is that many folk could be rescued with just one rope. A person could be rescued every twenty seconds, if a relay system operated, it would need to be able to bear the weight of some quite heavy people, they could descend one at a time, others descend up to three at a time in sequence. An inventor who could devise a suitable 'hands-off' breaking system, could well find a ready market. Perhaps automobile seat belt web, rolled into a large coil would be more suitable than a rope. The sums look promising, (Pi x 'r' squared, the area of the coil, perhaps three mm thick belt web. The Sears Tower is only 422 meters, 42,200 cms. x 0.3 cms =12660 square cm. allowing for a central hub, 1.4 meter overall diameter would suffice. A strap 0.3cm thick and say 10 to 20 cm wide and I suspect you could rescue an entire herd of elephants from the roofgarden. Change that to six to ten rescues a minute. with a well thought out system. The insurance premium reduction would pay for it many times over, as one would hope and pray it was never deployed.

....as far as I remember, each person would buy his own parachute - if that was his wish......

The rope idea is excellent, but needs a lot of "in-house" prior coordination and investment, which I truly doubt will never come in any skyscraper ever.....with the parachute - your life is in your hands.....!

Andy, I note you are a 'philosopher', how true. No Architect or Building Contractor would want even the slighest suggestion of any notion of 'danger' being attached to the concept of 'high rise'. The latest work on self assembly carbon nanotube ribbon may have an application here. Van der Waal forces (moisture) ensure the carbon sticks together. We have all seen how chewing gum can stretch, suppose we include 'bucky-balls' into the mix, nano scale ballbearings between the fibres? perhaps an escape rope that had sufficient strength and stretch, might be of use here. A bungee-jump without the 'bounce'? I distrust parachutes, they sometimes fail to deploy correctly.

I thought of having a rope which is long enough to get around the flaming section. Lower yourself to below the fire and then use a hammer to break the window, enter, and go down the stairs.

Grab that fire hose and jump!

Sadly, most buildings are built with the windows above each other, so unless you are lucky and one side of the building is unaffected (the stairs on that side then may be free of smoke, you are going to have to fight thru the flames (hanging onto your rope!) to get to a lower floor....it might even burn your rope thru first....

Then if you are a fit and not overweight 40 year old or less and have practised rope climbing (descending!) a lot.....you may be OK.....

Although I hate heights, (I am also 60 years old, 10KG too heavy and not wonderfully fit....)I think that I might be able to jump with a 'chute if the fire got really going (assuming that I laid the cash out for the 'chute in the first place!!), but as I am retired, I rarely go into high rise buildings, I even have a trailer (caravan for Europeans!) for holidays......now I do go on ships a lot where fire really IS dangerous!!! But a chute is unlikely to be of much help!

I thought maybe a steel cable might solve the burn-through problem. Definitely would need at least a hundred feet or two to get down low enough to be pretty sure of being below the flames. It should have some kind of harness to prevent slipage or uncontrolled descent. It should also have some kind of brake and end stopping system as well. It will need to be able to descend quickly to limit occupant heat exposure.

One problem with a parachute is that it is likely to get caught on something. It could then tear, spill the air out, or get stuck and leave us hanging precariously.

Some years ago I was invited to Open the Degree Show at our National College of Architecture, The A.A. by Professor Sand Helsel. This is a superb project for a post graduate or even undergraduate. I have seen 'exterior' lifts. they are quite practical as office space is left free to rent. and also practical in a fire. Yoo.com are currently building the tallest UK structure in Leeds. John Hitchcox the CEO is a friend from the 1970's I had a hand in his education, blah blah, I shall link him to this chat room, and let's see if some brilliant ideas emerge. get cracking team. Ideas could become reality. but let's forget the spiderman scenarios. P.S. the old lift machinery in most of America's Oldest Sky Scrapers are still ready to do another century of good service. Ah! that almost brings a tear to my eye. Engineering at it's best.

Ah, it does bring a good feeling to know that the members of the engineering and the scientific research professions are and have been dedicated to doing good work.

Indeed so, and long may the tradition continue. Where safety is concerned, engineers never tolerate compromise. I doubt there is much 'guesswork' involved in designing a parachute. Excellence is not achieved without great effort.

...not to mention the up and downdrafts that are around buildings will make your trip pretty tricky with a 'chute!

God forbid that we see another 9-11, but in such a case, I think that relying on any "built-in-system" of the building is not a good plan......it will most likely be damaged beyound further use......so although I realise ALL of the problems that may occurr when using a chute, not the least of which will be my relative inexperience of using one, at least it would be something outside of the control and damage caused by terrorists!! (Assuming that I was not disintegrated at ground zero and neither was my,as yet un-bought 'chute....)

I can assure all concerned that if another working system still exists in the building concerned to bring me to ground level without jumping with a 'chute, that will get used first!! But as most high rise buildings have nothing that even approaches that sort of safety feature and the building managers are most unlikely to start building extra safety in just because of a few Engineer Bums like us and 9-11........I still like my parachute idea best.....in spite of all its shortcomings.....

If it was possible to ask those poor people who sprang to their deaths on 9-11, I have a feeling that a lot would have taken the chance on an unused parachute....

I almost forgot, for building managers I would expect Parachutes to be cheaper in the long run than anything else with regard to ease of implementation and speed, and in spite of the numbers needed, all you really need is storage space and a large one-off payment to the supplier.....plus you could even charge extra rent for them! Also, a chute built for a single usage could be cheaper, lighter weight material and therefore physically smaller than one built for many, many jumps....one could imagine that such a chute might also be usefull in light aircraft.....

Good on you Andy, And what is more a 'chute' can be tested with just a sandbag or safer still bags of water. If I had to design my own chute, my first option would be a multiple chute set-up on a long line. safety in numbers. Those unpredictable updrafts and downdrafts could scupper a single chute. I saw ripstop nylon fabric weighing a mere 2.2 oz. per square yard (75 grams per square meter), and 60 inches in width.

Check out:- http://www.pictureprettykites.com/newppk/details.asp?Path=649 (Sorry, link no longer available)

'Spinnie' Kites, each kite in line spins in counter-rotation. That might give extra drag, They are quite cheap, and one could always chuck one over the side of a tallish building with a waterbag payload to see what happened, or tie it to a fisherman's spring ballance and get someone with a pick-up truck to give you a ride at different speeds. No chance of them collapsing, as a fibreglass circular rod forms a hoop to keep the spinnies open. Better to land and even break a bone or two, just one jumbo kite would probably save your life. more save broken bones.

Science is about checking the theory, I figure that a chute fills with air, and then the air passes round the obstacle? Also that a propeller may? be better, because air passes through, not round, and has to do a bit of 'work' That leads to an interesting question, namely "would a bad propeller have more drag, than a good one?" (more work to do?) Suck it and see time!.... small scale to start with..... Who knows? we might be on to a useful piece of kit, or maybe not? I am sure sky divers could test it out, with two regular parachutes to do the actual slowing down, (one spare) They could cut the long line of props away well before the safety altitude. (Not before extensive 'dummy' tests though! those spinning props might be well dodgy? or just fly appart, ripped to shreds by the slipstream)