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Canopy Cutter Discussion

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Collected by: Dave Reinhardt acrodave@tnn.net

The Question:

I've been thinking about what to get for an emergency canopy cutter in case of a flip-over. While at Sun & Fun the other day, I looked for one of those military canopy knifes (as seen in Tech Tips) but no luck. What other solutions have been used? Any tips for attaching it in an S1S?


The Answers:

The Grob airplanes (G-115) and motorgliders have beautifully made little canopy-axes provided, and mounted on the floor with a quick release clamp. The axe is a reasonable size, hefty yet small. You might want to check with the Grob importer to see if you could get one from there.


The ZLIN 142C I fly also has a small canopy axe in a leather holster, mounted overhead on the center frame of the canopy. Zlin's are distributed by Zlin Aerospace in Barrie, Ontario, phone # 800-959-6988 (or 705-722-3522)


For many years I have been using a "Life Hammer" originally produced to be sold to users of the autobahns. It is a small hammer with a 2 - 3/4ths inch wide head with both ends of the hammer head tipped with hard conical steel (1/2" diameter) The overall length is 7". The handle has a recessed "hook knife" which is designed to cut seat belts or shroud lines of a parachute. It fits into a Cordura holster fasted by velcro and with a belt loop for use on my parachute chest strap. It also can be obtained in a hard plastic gripper fitting which could be bolted to an airframe. I prefer the holster as it is more flexible and less subject to catastrophic failure. ( A loose hammer could ruin your day). In addition I want the hammer with me if I depart the aircraft. I have had difficulty finding them until just recently. However, again there is a distributor for this German product. A catalogue company called Herrington of 3 Symmes Dr. Londonderry, NH. 03053 sells them without the holster but with the plastic clip device. I obtained the holster from Innovation Distributing, Santa Barbara CA. 93101 Tel (805) 568-0227.

One of my friends overturned in a Pitts S 1S in a soft field. She hung upside down, unable to slide the canpoy back for two hours. Had she been able to break out she would have suffered less. (The plane did not burn fortunately)


I remember seeing something that may be of interest here. There is a device that is small and looked just like a pen. The police use it to shatter windshields. I believe I saw it in one of those police/law enforcement/survival mail order catalogs. It is spring-loaded device that sends a small pointed metal rod through the glass, shattering it. Not sure how it would work on a canopy though.


That probably was an automatic, or spring loaded, center punch that can be bought at any hardware store. WalMart has them for $10. I saw one of these demonstrated on TV recently as a tool the police carry to shatter windows to remove people that are pinned in. They really worked in that demo. Just ask for a spring-loaded center punch in any hardware store tool department.


IAC President Dick Rihn found a great little device a few years ago; it's called the Life Hammer. I tried it out on a scrap canopy, one small hit and the canopy exploded. It is very light and small, it has a nice holster which can easily be mounted on your parachute harness. I have asked him to write an article and provide a source.


I used to carry one of these windshield breakers in my ambulance days. They work great, one or two strikes and the windshield spider-webbed. They also work great as a center punch for drilling out rivets!


The canopy cutter Budd Davison sells is identical to the one that can be made from the plans found in an early 80's SPORT AEROBATICS. I have a copy of them somewhere in my files, just don't know exactly where. It is a substantial piece of hardware, as Patty can attest. As I recall, the ad for the product Budd was selling quoted a price of about $250, which I thought was rather pricey. It does take a lathe and milling machine to produce. Heat treating and chroming add additional cost.


I have a Marine K-Bar knife in a sheath zip tied to the seat frame in my B. This knife can be bought new for $50 from a surplus store. It is certainly tough enough to deal with the canopy either as a lever or using the point. It also has many other uses such as digging a foxhole, disemboweling recalcitrant line guys or beheading front seat passengers. Not bad for $50!


A couple year ago at Sun 'n Fun or Oshkosh I found a guy selling knives and he had a plexi cutter that really shattered the stuff. The tip is very thick then ground to a sharp point. It only took a light hit to destroy a piece of plexi. He said it is the thick blade that does the trick. I have it tied to one of the tubes along the seat. Cost, about $40. Hope I never have to try it out.


Canopy cutters would seem to be a good idea to have in the cockpit. A recent series in "Warbirds" went over emergency items.

While a T-34 or T-28 may have the room to pack such stuff, my Eagle seems a little small. So the question is, what would you put in the plane?

Re-read the articles (it was a series of three). Carry anything important in your pockets or sewn into your chute harness. Otherwise it -will- get lost. I carry a sturdy, short bladed knife upside down on my parachute harness. It suffices as a canopy breaker and also for a shroud cutter. If anyone is -really- interested, I'll write a treatise for the group here. The point being, as I found out in my own crash, that canopy cutters mounted to the airframe rely on the concept that the structure to which they are mounted stays where it belonged---not a valid assumption, as I found out when about 2/3rds of the structure was simply peeled back like a sardine can. If my chute worn cutter is not where it belongs, I'm probably dead anyhow. (almost been there...)


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Last Update: Sat Aug 29 16:11:25 2009


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