On Sunday night I showed a picture and linked to Air Traffic Control tapes of the latest “parachute save” involving a small airplane. This was the descent of a Cirrus SR22 aircraft that had lost engine power while flying over Long Island.
Fifteen years ago, in my book Free Flight, I described several of the aviation and technological pioneers who through the 1980s and 1990s were attempting to bring to the risky, technologically conservative world of small-plane aviation some of the digital-age advances that were then transforming nearly every form of manufacturing, design, and engineering. A central figure in that book was a lifelong pilot, and career-long NASA official, named Bruce Holmes.
Last night this same Bruce Holmes sent me a note about the back story to this latest parachute save, and about future areas for innovation:
You may recall, or not, from your research during the writing of Free Flight, that NASA supported the whole airplane parachute technology effort led by the good people at Ballistic Recovery Parachutes (BRS) through Small Business Innovation Research (SBIR) funding.
Indeed I do recall! The BRS company, based in Minnesota, came up with the small “ballistic parachutes” that were first used in home-built and experimental planes and later adopted in the Cirrus line of aircraft. Cirrus is still the only manufacturer of normal “certified” aircraft to include parachutes as mandatory, built-in equipment. Largely for that reason, the SR22 has been for years the best-selling small plane of its type around the world. Cirrus still produces its airplanes in Duluth, Minnesota, including the SR20 I bought when it first came on the market 16 years ago and SR22s like the one I have been using for our American Futures project. (I have no connection with Cirrus except as a customer.) The Cirrus company is now owned by the Chinese government’s aviation consortium, but that is a different story.
Back to Bruce Holmes:
I am proud of my former NASA colleagues for their support of these endeavors. I am also proud of our friend and entrepreneur of the Cirrus industry, Alan Klapmeier, who stated early on, “the cost of a mistake in the air should not be death (sic),” or close to that sentiment.
One of the technical backstories that inspired our NASA folks at the time (circa 1995 or so) to support the BRS visionaries was our NASA and DoD experience in the use of “risers” on parachutes designed to slow down hypersonic “things” re-entering from suborbital or orbital trajectories. The basic idea is that if a parachute were to fully inflate at hyper- or supersonic speeds, the canopy would disappear in a puff of dust due to the extreme forces at those speeds. So the “riser” (a small donut-shaped devise riding on the parachute cords) provided a way to manage the energy entering the canopy of the parachute slowly so as to make it possible that at the highest speeds and energies, the canopy would act like a drag chute (mostly closed), then as speeds slowed from supersonic to subsonic, the riser on the parachute lines would lower toward the vehicle, gradually let more air into the canopy so as to allow the chute to fully inflate at safe speeds and let the payload down slowly.
Yes: I told the story of “the slider” in Free Flight. The illustration at the top of this post is from an engineering-achievement award citation given to Boris Popov, founder of the BRS company that created the chutes, showing how the slider works in a Cirrus deployment.
Well, here we are a few decades later with numerous stories of Cirrus BRS saves. The news is gratifying and at the same time, a bit disconcerting: Why all the engine failures? [Yes, good question — though the rate appears to be slightly less frequent than for the general aviation fleet as a whole.]
I am in DC this week for a workshop hosted by NASA and the FAA that rejuvenates the concept of democratized air mobility. Where in the past, we looked to the physical parachute for safety, today, we can look at digital electronics as a “parachute” for future air vehicles. Further, aviation will migrate to electric propulsion (my opinion, based on laws of physics and laws of the marketplace). We still need a breakthrough in battery energy densities or in practical hydrogen fuel production, among other issues. Perhaps this electric migration will mitigate against the question: Why all these engine failures?!