A jammed canopy and aircraft on fire.
Thread Starter
A jammed canopy and aircraft on fire.
In the early 1950 era, the United States Air Force installed canopy breaker tools in some of their aircraft following a series of fatal accidents involving F-80 Shooting Star fighters. These aircraft had carried out high speed rejected takeoffs which resulted in over-runs.
In some cases damage caused by over-runs into rough ground caused the canopy to warp and locking devices to jam, which in turn prevented pilots from exiting the aircraft. Fire caused the death of some pilots trapped in the cockpit. In those days ejection seats were not capable of safe ejection on the ground.
Following the USAF decision to install specifically designed canopy breaker tools, the RAAF conducted their own trials at the Aircraft Research and Development Unit at RAAF Base Laverton, on Sabre and Vampire fighters. These proved successful and canopy breaker tools were later installed on CT-4, Macchi and PC-9 training aircraft.
The first life was saved when a Sabre had an engine failure due to a bird strike on take off causing the pilot to forced land straight ahead into a rice paddy. The aircraft caught fire and initially the pilot was unable open his canopy more than an inch due to a warped canopy rail. He quickly extracted his canopy breaker tool from its position in the cockpit and was able to break through the canopy and escape without injury.
Some Light Sports Aircraft (LSA) have one piece canopies that slide on rails and are locked with one or two over-centre levers. These canopies can be quite heavy to operate. The over-centre levers are operated by the pilot and his passenger.
If the pilot is flying solo, he must lean well over to the passenger side to actuate that canopy locking lever as well as his own. The close tolerances of these locking devices mean they are often stiff to lock and unlock. The relative fragility of LSA design means it doesn't take much of an impact to jam the locking devices or warp the rails making the canopy impossible to open. The term "Death Trap" comes to mind.
It takes little imagination to wonder how the occupants could escape if the canopy jammed after a forced landing where the machine became upside down on touch down on rough terrain.
Barring the current availability of a dedicated aircraft canopy breaker tool that has been thoroughly tested before being put on the market, pilots of LSA, whether home or ready built, would be wise to equip themselves with a suitable device robust enough to break through the glass canopy in an emergency.
In some cases damage caused by over-runs into rough ground caused the canopy to warp and locking devices to jam, which in turn prevented pilots from exiting the aircraft. Fire caused the death of some pilots trapped in the cockpit. In those days ejection seats were not capable of safe ejection on the ground.
Following the USAF decision to install specifically designed canopy breaker tools, the RAAF conducted their own trials at the Aircraft Research and Development Unit at RAAF Base Laverton, on Sabre and Vampire fighters. These proved successful and canopy breaker tools were later installed on CT-4, Macchi and PC-9 training aircraft.
The first life was saved when a Sabre had an engine failure due to a bird strike on take off causing the pilot to forced land straight ahead into a rice paddy. The aircraft caught fire and initially the pilot was unable open his canopy more than an inch due to a warped canopy rail. He quickly extracted his canopy breaker tool from its position in the cockpit and was able to break through the canopy and escape without injury.
Some Light Sports Aircraft (LSA) have one piece canopies that slide on rails and are locked with one or two over-centre levers. These canopies can be quite heavy to operate. The over-centre levers are operated by the pilot and his passenger.
If the pilot is flying solo, he must lean well over to the passenger side to actuate that canopy locking lever as well as his own. The close tolerances of these locking devices mean they are often stiff to lock and unlock. The relative fragility of LSA design means it doesn't take much of an impact to jam the locking devices or warp the rails making the canopy impossible to open. The term "Death Trap" comes to mind.
It takes little imagination to wonder how the occupants could escape if the canopy jammed after a forced landing where the machine became upside down on touch down on rough terrain.
Barring the current availability of a dedicated aircraft canopy breaker tool that has been thoroughly tested before being put on the market, pilots of LSA, whether home or ready built, would be wise to equip themselves with a suitable device robust enough to break through the glass canopy in an emergency.
Last edited by Judd; 21st Feb 2016 at 04:32.
Have a read here, watch the video:
Bruce Swayze's RV-7A
If you are really worried that you wont have the strength to open you canopy in a fire, or that the you will flip in onto its back without breaking the canopy go an buy one of the little plastic hammers with the point.
Bruce Swayze's RV-7A
If you are really worried that you wont have the strength to open you canopy in a fire, or that the you will flip in onto its back without breaking the canopy go an buy one of the little plastic hammers with the point.
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You would be a fool to own a canopy type aircraft and not have a breaker installed/available to you.
Even on aircraft with a door they can be useful. I saw the aftermath of a crash where the door deformed and the occupants could not get out to escape the fire. Fortunately some external assistance arrived to break the windshield and get them out. Other than the engine there was not much left of the aircraft once the fire took hold.
Even on aircraft with a door they can be useful. I saw the aftermath of a crash where the door deformed and the occupants could not get out to escape the fire. Fortunately some external assistance arrived to break the windshield and get them out. Other than the engine there was not much left of the aircraft once the fire took hold.
Folks,
A welders chipping hammer makes a great canopy breaker tool, cheap, cheerful and very effective.
If you want something a bit more up market, Smith and Wesson have a nifty little spring loaded breaker, that also has a safety knife to cut seatbelts, and available from shops who supply police, RFFS and similar. Don't buy one of these offshore, as it get caught up in the prohibition on "flick knives".
Aircraft Spruce and Specialty also sell one that has a nice mounting bracket.
Tootle pip!!
PS: The name of the S&W device is the "First Response".
A welders chipping hammer makes a great canopy breaker tool, cheap, cheerful and very effective.
If you want something a bit more up market, Smith and Wesson have a nifty little spring loaded breaker, that also has a safety knife to cut seatbelts, and available from shops who supply police, RFFS and similar. Don't buy one of these offshore, as it get caught up in the prohibition on "flick knives".
Aircraft Spruce and Specialty also sell one that has a nice mounting bracket.
Tootle pip!!
PS: The name of the S&W device is the "First Response".
Last edited by LeadSled; 21st Feb 2016 at 05:02.
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no one,
The 'little plastic hammers with the point' to which I think you are referring are specifically designed to deal with 'toughened glass'.
Not laminated glass or even 'perspex'.
I stand to be corrected, but I strongly doubt they'd work with a blown perspex canopy.
What is needed is something more substantial - along the lines of that developed for the RAAF Sabres, as mentioned above.
Going back a bit further, the jemmy-like tool that you see clipped to the inside of a Spitfire door was also designed for that purpose.
p.s. LeadSled, the S&W spring-loaded tool you mention was also designed to attack 'toughened glass' at its 'achilles heel',
i.e., its relative rigidity and inherent tension.
I'd be interested to hear if they do actually work effectively with Perspex. Once again, I have my doubts, though.
.
The 'little plastic hammers with the point' to which I think you are referring are specifically designed to deal with 'toughened glass'.
Not laminated glass or even 'perspex'.
I stand to be corrected, but I strongly doubt they'd work with a blown perspex canopy.
What is needed is something more substantial - along the lines of that developed for the RAAF Sabres, as mentioned above.
Going back a bit further, the jemmy-like tool that you see clipped to the inside of a Spitfire door was also designed for that purpose.
p.s. LeadSled, the S&W spring-loaded tool you mention was also designed to attack 'toughened glass' at its 'achilles heel',
i.e., its relative rigidity and inherent tension.
I'd be interested to hear if they do actually work effectively with Perspex. Once again, I have my doubts, though.
.
Last edited by Stanwell; 21st Feb 2016 at 05:43.
Stanwell,
Have a read of the link I posted and view the video at the bottom. This was a "test" done with on an actual canopy. While the little plastic hammers are sold for cars with toughened glass they do pretty well on the perspex given repeated efforts. The trick is that once a crack is formed you have to work it along bu hitting again ahead of it. The spring loaded breaker thing didn't do too well.
no_one
Have a read of the link I posted and view the video at the bottom. This was a "test" done with on an actual canopy. While the little plastic hammers are sold for cars with toughened glass they do pretty well on the perspex given repeated efforts. The trick is that once a crack is formed you have to work it along bu hitting again ahead of it. The spring loaded breaker thing didn't do too well.
no_one
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Hmm, OK.
Let's see what others have to say.
Thankfully, I've no personal experience having to deal with such aircraft-related incidents.
But... It's no doubt better than futilely thumping at it with your fist!
.
Let's see what others have to say.
Thankfully, I've no personal experience having to deal with such aircraft-related incidents.
But... It's no doubt better than futilely thumping at it with your fist!
.
Last edited by Stanwell; 21st Feb 2016 at 06:17.
When I flew in UnZud, all aircraft were equipped with a small axe/hatchet/tomahawk - specifically for the purpose of dealing with perspex windows/windscreen to exit an aircraft in an emergency.
Its a practice I carried over on my returned to Oz! Not really required in the Bo though because of the multiple emergency exits.
Its a practice I carried over on my returned to Oz! Not really required in the Bo though because of the multiple emergency exits.
In the FAR certified Liberty XL2 there is a safety hammer located behind the passenger seat in the compartment but not in the pilots seat. Given that you cannot reach the hammer from the right seat, the control seat is therefore the left seat only in the flight manual. Obviously they view this hammer as important.
As a former first responder I learnt that consumer car window breakers are notoriously unreliable.
The sharpness and hardness of the tip is key.
Relying on (any) car window breaker to break a Perspex canopy is not prudent.
Mickjoebill
The sharpness and hardness of the tip is key.
Relying on (any) car window breaker to break a Perspex canopy is not prudent.
Mickjoebill
Thread Starter
It's no doubt better than futilely thumping at it with your fist!
Within weeks we had two prototype knives ready for testing. First I had to convince the brass at Department of Air in Canberra that the canopy break-out knives were a Good Thing. That done, someone had to decide which aircraft should have them. I decided to arrange for the knives to be tested on real aircraft and, working on the theory that a picture is worth a thousand words, the tests would be filmed. The Aircraft Research and Development Unit (ARDU) at Laverton had Sabres, Vampires and Macchis.
These were among the types I envisaged should be equipped with the knives. However, canopies were expensive and there was no way that the CO of ARDU was going to allow me to smash one, just to test a knife. But as luck would have it, there were several canopies in store that had been damaged or badly scratched. They included one Sabre and one Vampire Mk 31 (single-seat) canopy.
The next problem was to find someone willing to risk flying shards while smashing his way out. I was happy to do the job myself, but being a coward who couldn’t punch his way out of a paper bag, I felt the whole project could be jeopardised if my failure to break out was recorded on film. What I needed was a real tough bloke (RTB) with the strength of 10 good men -- if a RTB failed to break through the canopy, then the average fighter pilot would have no hope, even when charged with adrenalin. So we needed a strong knucklehead - and I knew just the right Knuck for the job.
Flight Lieutenant Peter Middleton, DFC, had flown Meteors during the Korean war and when I first met him in 1953 he was a Fighter Combat Instructor at No 2 OTU at RAAF Williamtown. Tall and strongly built, he had a degree in martial arts -- a Black Belt in Karate, I think -- not the sort of chap to upset.
Middleton was now adjutant of Base Squadron at Laverton. Bored behind a desk, he jumped at the opportunity of some excitement other than strutting the parade ground with a ceremonial sword. And if Pete was unable to break out through a Sabre canopy, no one else could.
So the stage was set. Pete would dress the part with a Bone Dome, flying suit, gloves and the knife. The canopy would be locked with Pete at the controls and, on the order, would attempt to break his way out using the knife. The event would be recorded on film and the results sent to Department of Air. If all went as planned, money would be allotted for knives to be installed in various RAAF aircraft. Lives would be saved, and I would be a hero for thinking of the idea. I would, of course, conveniently forget the concept came from the USAF and that some hard working airman in a cold and draughty hangar actually fashioned the knife. Minor details!
The day dawned and Peter Middleton climbed a ladder to the cockpit of the Sabre. One inside, he strapped in and closed the canopy. The airman from the RAAF School of Photography focussed his Leica and held up his sign for Take One. There could be no second chance if a stuff-up occurred -- condemned canopies were in short supply.
Suddenly Middleton waved furiously, and wound open the canopy. He said he had a good idea. The camera man looked up, puzzled, his finger poised. Middleton called out to the waiting throng (all the airmen in the ARDU hangar had downed tools to watch) that before using the knife he would first try to karate his way out -- an event somewhat akin to those fellows who break bricks with one mighty blow of the hand. This was going to be interesting; the camera man refocussed his lens.
With a fearsome shout, muffled by the closed canopy, Middleton lashed out with the side of his gloved hand. The onlookers watched, open mouthed. Then admiration turned to unrestrained laughter as Middleton swore a frightful oath, shaking his hand in agony as his blow bounced harmlessly off the canopy. His muffled curses were terrible to hear. So much for smashing a load of bricks at one blow! There was a short delay for smoko while a nurse treated poor Pete’s badly bruised hand.
The show was soon back on. This time, Pete had the knife in his hand and looked mean. Already embarrassed by his failure, he was not going under easily this time. At the sign of Go, the camera rolled, and Middleton attacked the canopy with the savagery of Ghengis Khan. Huge cracks appeared within seconds and after half a dozen more blows, Middleton had beaten through and heaved his way out of the splintered wreckage. I was delighted. One more canopy to go!
This time it was the Vampire with tough, double width glass which I thought would prove more difficult. Again, in front of the now admiring airmen, Pete was through the canopy in less than 35 seconds. In fact his knife blows were so effective that the canopy frame actually lifted off its rails. Applause -- another smoko, then everyone went back to work. Pete, still nursing a bruised hand, returned happily to his office and ceremonial sword.
The RAAF Mirages carried a canopy breaking tool. It was similar to a heavy duty dagger with a very short thick blade cut off at 45 degrees. On one occasion, when a canopy was due for replacement, an exercise was held to test the tool. It took considerable effort by the pilot to break the canopy. Then even more to make a large enough hole in order to escape.
(The aircraft also carried a tool on the coaming able to puncture the life raft within the ejection seat. In case it accidentally inflated in flight.)
(The aircraft also carried a tool on the coaming able to puncture the life raft within the ejection seat. In case it accidentally inflated in flight.)
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My P2002JF has a hefty, sharp little hammer accessible from the pilot's seat but not so readily reached from the RH seat. Don't know if it's only the VLA certified versions which have it, or whether the Tecnam LSAs also have hammers.
Like the OP, I was (and am) extremely nervous about a number of the canopy designs around. There's no perfect system but I looked for decent roll protection as a starting point, trading a slight amount of visibility to get it. There's a video of a factory crush test of the P2002 cabin and it's impressive for a light structure.
Like the OP, I was (and am) extremely nervous about a number of the canopy designs around. There's no perfect system but I looked for decent roll protection as a starting point, trading a slight amount of visibility to get it. There's a video of a factory crush test of the P2002 cabin and it's impressive for a light structure.
p.s. LeadSled, the S&W spring-loaded tool you mention was also designed to attack 'toughened glass' at its 'achilles heel',
i.e., its relative rigidity and inherent tension.
i.e., its relative rigidity and inherent tension.
I did manage to crack an old side window from a light aircraft, suspended between tow bricks.
In any event, I would recommend the welder's chipping hammer, around $12.00 or so from Bunnings, and as effective as the USAF standard canopy breaker --- indeed, a very similar size and weight.
Tootle pip!!
Surely not an issue for RAAF pilots of days gone with their service pistol handy? 
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Around 1988, a similar demo was done at 2FTS with an old Macchi canopy. The victim was (I think) Leroy, a big fella, wearing the full kit of g-suit, Mae West, all strapped in, and with the canopy locked shut in the Perth blazing sunshine.
The word was given, and he started to hit the perspex with the dagger.
And Hit
and hit
and hit
and (puff puff) hit - the movement was severely limited by elbow room in the Macherschmidt, and little momentum could be built up. He changed grip, changed the strike area, and dissolved into a sweatball. Still he punched away until, many minutes later, exhausted, a small hole appeared, and with lots more effort he got it big enough to get his hand through.
It took a serious amount of time and bruised elbows and wrists to make the hole big enough for a helmet to fit through. Those canopies were TOUGH!
I don't remember whether Leroy actually got through the hole, or we opened the canopy to allow him to stay alive, but the end result was that we reckoned that the best use for the dagger in a canopy-jammed fire would be to slit your wrists to speed it up a little.
The word was given, and he started to hit the perspex with the dagger.
And Hit
and hit
and hit
and (puff puff) hit - the movement was severely limited by elbow room in the Macherschmidt, and little momentum could be built up. He changed grip, changed the strike area, and dissolved into a sweatball. Still he punched away until, many minutes later, exhausted, a small hole appeared, and with lots more effort he got it big enough to get his hand through.
It took a serious amount of time and bruised elbows and wrists to make the hole big enough for a helmet to fit through. Those canopies were TOUGH!
I don't remember whether Leroy actually got through the hole, or we opened the canopy to allow him to stay alive, but the end result was that we reckoned that the best use for the dagger in a canopy-jammed fire would be to slit your wrists to speed it up a little.
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Not quite the same thing, but all the Spitfires I flew (Mks I,II,IX,XIV, XVI and XXII) had a "jemmy" (crowbar about 18 in long) clipped to the inside of the cockpit side flap.
Never had to use one, but I would think the best way would be to use the chisel end to force the canopy side frame off the rails rather than punch a way through the perspex.
Never had any instruction on them at all !
Danny.
Never had to use one, but I would think the best way would be to use the chisel end to force the canopy side frame off the rails rather than punch a way through the perspex.
Never had any instruction on them at all !
Danny.
Last edited by Danny42C; 23rd Feb 2016 at 00:02. Reason: "Smilie" wouldn't work !
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Youtube
http://youtu.be/63eMVRQkM6c
Hardly scientific, and probably the centre pnch first helped the later use of small pointed hammer.
http://youtu.be/63eMVRQkM6c
Hardly scientific, and probably the centre pnch first helped the later use of small pointed hammer.
I think the stories of military canopies and their toughness, while interesting, do not really apply to the original question. An LSA is built to a light weight and the canopies are substantially thinner than than those of a military jet.
There are several "documented" trials of people using the small hammers that are designed for toughened glass on a light aircraft canopy.
EG:
I used my cracked canopy to test canopy exit tools - VAF Forums
Or
https://www.youtube.com/watch?v=fRvQ...ature=youtu.be
There are several "documented" trials of people using the small hammers that are designed for toughened glass on a light aircraft canopy.
EG:
I used my cracked canopy to test canopy exit tools - VAF Forums
Or
https://www.youtube.com/watch?v=fRvQ...ature=youtu.be