When I was 15 years old, I came across a magazine article explaining how jet engines work. It was 1947, and the technology was still fairly young. I showed the article to my buddy Walt. After perusing the cutaway views of turboprop, turbojet, and ramjet engines, we concluded that the ramjet was the simplest. “Hey, we can build one of those!” we said.
It so happened that our town, Enderby, in British Columbia, was putting in new water mains when winter struck. With the ground frozen, the workers were forced to leave four-inch-diameter pipes lying uninstalled along a couple of streets. We decided that for scientific purposes, Enderby should donate some of this material. We proceeded to liberate a length.
When we got it home, we drilled two holes, one on top and one on the bottom. In one hole we put a spark plug; in the other, quarter-inch copper tubing to serve as a fuel line. We connected the spark plug to an old tractor magneto on which we had mounted a crank for hand operation. From previous adventures we had acquired a single-burner gas stove with a built-in pump; we removed the gas tank and connected it to the fuel line.
Now we needed a source of moving air. We enlisted a couple of unsuspecting neighborhood kids and got them to blow into one end of the pipe. As they did, we injected a spray of gasoline through the fuel line and cranked the magneto, which caused the spark plug to ignite the gas. There was one problem: The heated gas flowed out both ends of the pipe, resulting in several singed eyebrows. Quickly running out of volunteers, we realized we needed a better source of air.
Walt had just completed a beautiful two-man bobsled, and we decided to enlist it in our project. We mounted the engine on two two-by-four outriggers on the right side of the sled. We fixed the magneto within reach of the “engineer”—the person who would sit behind the “pilot.” The engineer would hold the gas tank between his knees.
One beautiful, bitterly cold Saturday morning, we took the sled up my snow-packed street. We reached a point where the road sloped down for almost a mile, then angled off to the right. Since Walt was the better sled driver, he became the pilot, and I was named engineer.
I pushed off down the hill, then scrambled aboard, taking my position with the gas tank clamped between my knees. I cranked on the magneto with one hand and pumped on the gas tank with the other. As we gathered speed, we were rewarded with a plume of flame out the tailpipe, and a delightful moaning.
We were probably doing about 30 mph when the fuel line broke at its juncture with the engine. Gas sprayed back over my leg and the aft end of the sled, then ignited from the engine’s flame. We charged down the hill with fire streaking from my pants leg and the sled. “Stop this bloody thing!” I screamed.
Somehow we negotiated the hard right at the bottom of the hill, and Walt took us off the road and into a snowbank. I jumped off and jammed my leg into the snow, extinguishing the fire on my pants. Dumping snow on the sled, we put that blaze out too.
A survey revealed that the gasoline had burned only on the surface of my heavy wool pants and hadn’t damaged the fabric. The sled showed only minor scorching.
Although we hadn’t detected any significant thrust from our ramjet, the ride had been impressive. About a month later, while conducting further research, we read that most ramjets need to achieve a speed of about 375 mph to function properly. We never did find a hill steep enough.
—Gordon J. Twa