"If it ain't broke don't fix it." That's the Russian way.
Russian space engineers are renowned for simple, yet brilliant, solutions to complex problems that endure for decades. Everyone has heard the story of NASA wasting millions of dollars to develop a space pen before Russia solved the same problem using an invention dating back to 1564... the pencil. Fortunately for the reputation of American engineers this story is a complete myth, yet it persists to this day. However, the story of using giant matches to launch a rocket with humans on board? It's completely true.
At launch, the Soyuz rocket utilities four boosters circumferentially attached around a main stage, each with four combustion chambers and complemented by 12 small directional thrusters which are used to steer the vehicle in flight.
As pictured above, there are a total of 32 exhausted nozzles which must fire simultaneously during launch. If not, there would be a stream of unlit kerosene and liquid oxygen flowing from one nozzle into an open flame - this would have disastrous consequences for any astronaut or cargo unfortunate enough to be on board. In 1986, the Space Shuttle Challenger exploded violently when liquid hydrogen from the iconic orange external fuel tank instantly ignited as it came into contact with a flame emanating from the right booster engine due to a failure of the 'O-ring'.
Thus, it is absolutely crucial that all of these nozzles are ignited at launch. This problem dates back to the 1950s, when Russian engineers were working to develop the world's first intercontinental ballistic missile, the R-7.
To solve this problem, the Russians of yesteryear invented a simple yet brilliant solution: a series of giant match sticks.
To be more precise, the ignition system, pictured on the left, is a birchwood frame with an electric igniter on the tip. When the Soyuz is installed vertically on the pad before launch, technicians place twenty of these giant matches into the main chambers and 12 smaller matches into the steering engines.
The igniters are wired to the launch control system and when initiated a flame will burn through a small wire, killing a circuit which is monitored by the flight controllers. This ingenious system allows the launch control team to verify that each nozzle has a lit match inside by confirming that all 32 circuits have been broken.
Only when this has been verified will the launch team open the propellant supply lines, instantly flooding the chambers with several hundred tons of rocket fuel. The propellant is ignited immediately and the birchwood match system is simply burned up by the power of these incredible engines.
This decades old system has been in place for almost 70 years now and has seen the successful launch of over 1,680 rockets! Pretty good going for a technology which is little more than a piece of birchwood and a wire.
To get a taste for the power of a Soyuz launch, check out this video when a Facebook user stood way too close for comfort to the launch of Soyuz-MS11.
Much of this information comes from a fascinating article featured in Popular Mechanics.
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