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LSA chute failed to deploy during flight testing


techman

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This was on the cirrus forum... Sad.

 

Utah County deputy killed in small plane crash

Posted on: 10:19 am, September 6, 2013, by Meredith Forrest Kulwicki and Caroline Connolly, updated on: 09:35pm, September 6, 2013

 

SPANISH FORK, Utah - As police departments from across the state attended Sgt. Derek Johnson's funeral on Friday, the Utah County Sheriff's Office began mourning the loss of one of their own.

 

Sgt. Jay Lessley, 40, was killed Friday morning in a small plane crash near Spanish Fork airport.

 

 

"It's one of those things when you think, 'when is this going to end?'" said Sgt. Spencer Cannon, Lessley's long time boss and friend.

 

 

For about three years, Lessley had been piloting search and rescue operations for the Sheriff's Office. One of his many accomplishments, Cannon said, during his nearly ten year career with the department.

 

 

According to authorities, Lessley was off duty on Friday, volunteering as a test pilot, when the small experimental plane he was controlling suddenly crashed on private farm land west of the airport around 8:00 a.m.

 

 

Many of Lessley's colleagues were preparing to pay their respects to Sgt. Johnson when they were notified of the accident.

 

 

"Most people who were involved in this investigation of the crash today were getting ready to attend the funeral of Sgt. Derek Johnson this morning," said Cannon. "It just compounds the tragedy having it happen at a time when we're giving so much focus to another law enforcement officer, who heroically gave his life protecting his community."

 

 

Friday's ride was the fourth one Lessley had done for the plane manufacturing company, SkyCraft, which is based in Orem. According to company spokesman Paul Glavin, Lessley was testing the somewhat rare SD-1 plane, kit-built by a private owner.

 

 

"This is the first one built in the U.S. There are about 25 of them flying around the world," Glavin said.

 

 

Prior to taking off, Glavin said Lessley met with other company staff to discuss the flight path for the morning. However, about 15 minutes into the test, Glavin said Lessley veered slightly off course from the agenda.

 

 

"He was performing a maneuver called an aileron roll, where he rolls the airplane 360 degrees, and this is not an approved maneuver in the aircraft," Glavin said.

 

 

After one successful completion of the turn, onlookers were both surprised and excited by what the plane could do, but as Lessley attempted a second one, the aircraft responded differently.

 

 

"Then, on his second effort of performing this maneuver, something apparently did not go correctly," Glavin said.

 

 

While he would not speculate on what happened, Glavin said something could have malfunctioned inside the plane because it was not structured to operate in such a manner.

 

 

As the plane descended, Lessley attempted to use the parachute, but Glavin said it did not deploy properly.

 

 

"Based on the speed and condition of the aircraft, it was not a successful deployment of the parachute," he said. "It worries us that it did not work in this case and had tragic consequences, but it is very likely that the aircraft was not suited for an appropriate deployment of the parachute."

 

 

Lessley leaves behind a wife and daughter. The National Transportation Security Board is investigating the crash.

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Well, when an airplane is taken through a maneuver the airframe is not tested or approved for (aileron roll), there is no way to know for sure if this was a design deficit with the parachute system or just the airplane being in an attitude never envisioned for safe deployment in that airframe.

 

It will be interesting to see what the investigation shows, both by NTSB and the manufacturer.

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Well, when an airplane is taken through a maneuver the airframe is not tested or approved for (aileron roll), there is no way to know for sure if this was a design deficit with the parachute system or just the airplane being in an attitude never envisioned for safe deployment in that airframe.

 

It will be interesting to see what the investigation shows, both by NTSB and the manufacturer.

 

What is your source of implying that the BSR shouldn't deploy in a roll? It's supposed to work in a spin which likely has more severe forces. The rocket should shoot the chute out in any direction and it should deploy. We don't have much info on what went wrong so it's a little early to speculate and blame the maneuver.

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I'm not saying it won't, I'm saying there was not testing in this case to support than use of a BRS in this maneuver. If the chute deploys from the top like the CT, though, there is ample common sense reason that it might not work in a roll but be fine in a spin. I don't think the CT chute would do well being used from a rolling aircraft, do you?

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Andy,

 

Jim has staked out the position that "An aileron roll is a perfectly safe maneuver, of course." (direct quote)

 

Since he sees it as "perfectly" safe, he might be loathe to admit that such a safe maneuver might actually render the chute less effective.

 

For others, the image of the chute firing towards the ground from a rolling plane and possibly having its shrouds entangled in the empennage as the plane continued to roll is fairly easy to conjure up.

 

But I will agree this is all speculation at this point. So far as I know the Cirrus CAPS was tested up to 130k or so and also in a spin. I do not believe it was ever tested while rolling, so how it would perform in that regime is also mostly speculation.

 

However, I will speculate that had this pilot not yielded to the temptation to perform "perfectly safe" aileron rolls on that day, he might very well still be alive today.

 

Who knows? He might have read about how safe they were on this very forum, or the Cirrus Owner's site where a virtual clone of this discussion began after a YouTube video of a Cirrus doing rolls was posted.

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Does anybody know how many actual planes are used to test chutes? I know alot of testing is with similar weight ballast and not with actual planes. While weights and even tumbling weights are tests, I wonder how things like wings and engines impact chute performance.

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I found this, re: the Cirrus:

 

Inflight Tests

Numerous inflight deployments were made over a six-month period that included deployments from a spin, stalls and speeds up to 133 KIAS. After each CAPS deployment the test pilot would release the parachute and fly away so the airplane could be used for the next inflight test.

 

 

Complete CAPS Guide here: http://cirrusaircraft.com/static/img/CAPS_Guide.pdf

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Jim has staked out the position that "An aileron roll is a perfectly safe maneuver, of course." (direct quote)

 

Since he sees it as "perfectly" safe, he might be loathe to admit that such a safe maneuver might actually render the chute less effective.

 

There is no bases or need to insinuate that I have a bias toward one because of something that is unrelated. They are two totally separate issues.

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I'm visualizing a situation where one (or both) aileron is damaged or non-working and the aircraft goes into an uncontrollable roll. This is not a far fetched scenario which could occur. My thought is BRS and/or the manufacturer would consider this when developing deployments in various aircraft? Of course there are slow and rapid roll rates. I can also visualize the shrouds being wrapped around the fuselage and have this looking like the scrap piece of wood I keep with surveyor string rolled around it!

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I think manufacturers visualize all sorts of bizarre deployment scenarios.

 

The main reason for such a powerful rocket is to get the chute clear of the airframe and it's gyrations to allow it to fill gradually via the reef cutters, yet unimpeded by the motion of the plane.

 

So, I'd like to think the chute would function while inverted, possibly even while rolling.

 

Yet if one is well outside of the plane's performance envelope, in a region that has never been tested, there's probably additional risk.

 

I'm thinking of the minimum altitude for a successful pull. I'm sure BRS has carefully measured the altitude loss from deployment to stabilized descent in a variety of situations. But as I mentioned before, suppose the plane is inverted and rolling and the rocket fires straight down? This clearly could be the situation in a loss-of-control scenario, and as you've said. If the BRS did work, how much additional altitude would be required to get stabilzed under canopy? While BRS may have envisioned such deployments, it's unlikely they could have tested for each and every such scenario - you're safest bet is probably to pull while still within the plane's normal envelope, and not wait until things are really, really bad.

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I think all of us would agree that straight and level and at or below maneuver speed is a good place to pull the chute. The CAPS paper you cited, which we may find informative but is focused on Cirrus, even says that at speeds above it's rated limit it has worked.

The paper said loss in a spin was @900 feet (I'd have to relook to be certain) and that was in a Cirrus 20, if I recall correctly. We don't have any such info posted by FD so it's hard to know where we'd be, but it would surprise me if we lost more in a spin.

Even though real world testing has likely not been done in all scenarios, I'd have thought that computer modeling would let one make some assumptions about some situations. I can't imagine it would be all that hard to model a rolling aircraft and show likely results with a chute deployment. Maybe someone can do it in X-Plane. Does X-Plane have any aircraft where you can deploy the chute?

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