Pilot Seat Slides Back Occasionally on Rotation

Guest Discussion
#1

Recently I had what felt like a near fatal incident. I have occasionally had this seat slide back a couple times part way and am in the habit of jiggling it and pushing it back and forward to make sure it’s locked. I have had a Cirrus service center look at it and they found no issues. I am aware of several fatalities in the 1990s in Cessnas with a similar issue.

Has anybody else had this issue?

I am short statured so my seat is close to fully forward. At 5 knots below rotation seat slides back where I can barely hold the yoke and I have lost contact with the rudder pedals. The slide back is the whole way, maybe 2 feet or 20 inches? I can hold the yoke and touch the throttles. So choice is to pull throttle back and then try to pull seat forward as plane is veering left on runway and could go into ditch due to P forces, or to hold tight a couple seconds and pull the yoke and hope to rotate.

I chose to rotate and it flew uncoordinated but fine so once a few hundred feet off ground was able to load AP and have it fly and then pull up the seat and get organized. A seat that moves away from the controls is disconcerting for a single pilot operation under Bravo.

Anybody else with this experience? I have contacted Cirrus and am working on the issue. Thanks,

Kirk

#2

Be sure after you position your seat that the bar you pushed up to move the seat is positioned fully back down. If it is partially up the seat is not locked. There is an obvious difference in the position of that bar between locked and not locked.

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#3

Kirk,

What Brian said.

But if you are a member, it is much better to post on the Cirrus Forum rather than the Guest Forum. Many (?most) members don’t look at the Guest Forum and this issue is one that is important for all Cirrus pilots to read about.

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#4

I am a member and was logged in but never post so I couldn’t figure it out sorry.

I appreciate the feedback about the bar and will try that. Feel free to repost on the member forum. I am a member and will try to navigate. On my iPad I think it was more difficult but thanks!

#5

We discussed an accident in the member forums resulting from failure to secure the seat locking pins before attempted takeoff. Twisting in the seat while sliding can cause misalignment due to play in the seat tracks.

Report_98309_12_30_2020 9_08_50 PM.pdf (137.6 KB)

Reports from Parties to the Investigation-Master.PDF (1.1 MB)

Excerpt from docket:

image
image1792×828 152 KB

From the NTSB Report:

Analysis

The private pilot was taking off for a personal, cross-country flight. He reported that, at rotation, the pilot’s seat “abruptly slid backwards to the outermost distance from the controls.” As a result, the pilot could no longer reach the pedals to maintain directional control, and his aileron input could not counteract the airplane’s left-turning tendency. The airplane subsequently departed the left side of the runway, struck trees and shrubs, and then came to rest upright. The wings, fuselage, and empennage sustained substantial damage.
According to the pilot, except for the pilot seat, the airplane performed as designed with no other anomalies noted. Examination of the pilot’s seat revealed no anomalies with the installation, dimensions, or operation. The seat moved freely fore and aft with no binding or anomalous operation noted. During postaccident functional testing of the seat, when twisting forces to the right were applied to the seat and while being slid forward, the seat position locking pin could be partially engaged, but not all the pins would seat, and the control handle would not go fully down nor could it be forced into position. Straightening or forward movement of the seat resulted in full pin engagement with the control handle in the fully down position. Given this information, it is likely that the pilot applied a twisting force when moving the seat and did not fully engage the seat position locking pins before initiating the takeoff, which resulted in the seat subsequently sliding back as the airplane accelerated during takeoff and the pilot’s subsequent loss of directional control.

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be: The pilot’s failure to properly secure his seat before initiating the takeoff, which resulted in the seat sliding back as the airplane accelerated during takeoff, his inability to reach the pedals, and the subsequent loss of directional control and impact with trees and shrubs.

#6

Failure to secure the seat sounds like blaming the pilot instead of the plane. I took the plane to a Cirrus center for this problem and no mention of not wiggling in fact I think they encouraged me to push it back and forth to so I don’t know what to make of it. No mention of this idea of the bar not being fully down —great thought.

I always find it interesting that some pilots no ,matter what the problem love to blame the pilot, I called the Cirrus in Duluth and spoke with their safety and service team and nobody told me pull the bar down.

Anyway, I am glad for the constructive feedback from COPA. The “failure of a pilot to secure “ a seat that shouldn’t not be secure sounds like blaming a rape victim for wearing a short skirt…but it’s par for the course with pilots…I guess it makes you feel like it couldn’t happen to you because your smarter etc… this is so common it makes one not interested in forums like this. Thanks for the guys who offered the constructive idea of paying more attention to the seat adjustment bar.

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#7

I am on the short side and I learned very quickly that the seat needs to be locked down after adjusting it. You can definitely tell when it is down and locked. There is a placard on the console advising that.

“CREW SEATS MUST BE LOCKED IN POSITION AND CONTROL HANDLES FULLY DOWN BEFORE FLIGHT”

Edited to add: I see Mark already pointed out the placard

I suggest taking a look under the seat to see how it moves and locks.

#8

This was good info with the NTSB thanks for that aspect, this is a cirrus defect thought not a pilot issue.

#9

Don‘t take it personally, but if the seat is not locked and you take off it is always a mistake of the pilot. Even if it‘s a defect you always have to check the seat before takeoff.

It‘s in the „Before starting engine“ checklist: SEATS, SEAT BELTS and HARNESSES - Adjust and Secure.

From my very flight 26 years ago i was taught to check if the seat is firm. If you try to slide the seat back and forth the pins will slide into the holes (and the bar will go down automatically).

You were lucky. If it happens at 100 ft AGL while you hold on to the yoke this can be deadly.

#10

Kirk,

This happened to me in 2002. It was about 10PM, I had accelerated to 65 knots and was about to rotate on the runway in New Garden PA when my seat slide all the way back. As it did, with my hand on the throttle, I pulled the throttle all the way back and was able to slide under my seat belt to reach the brake pedals just before I started to wipe out runway lights. I was shaking for about 30 minutes before I was able to finally depart. Cirrus issued a service bulletin regarding seat rail alignment after this, but I machined a piece of aluminum that I would slip onto my seat rail that would precent the seat from sliding back regardless. I used it for several years before I convinced myself that I had both engagement holes captured when the seat treadle bar was fully down…Scared me to death!..BTW, still flying the same airplane!

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#11

Did you check the seat according to the checklist before you took off?

#12

When you adjust the seat you should feel/hear the under seat adjustment bar kick back fully into its original downright position. You should also do the weird ass jiggle thing and feel the seat locked into place. If the seat slides on takeoff it’s 100% the pilots fault. It’s a simple mechanical device.

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#13

I agree it’s very serious. But I have taken it to a cirrus technician and called Duluth and spoken to the head of service, nobody had mentioned the bar. I do push it back and forth and make sure it seems locked. But intermittently, in a plane with. 650 hours the seat flies back. I do believe it’s likely an issue somehow more for pilots with seats forward.

I had spent an hour on the phone just 2 hours before this flight. I put a hard suitcase behind the seat thinking that would keep it from sliding if it did. This had been an intermittent problem not a certainty. I am just saying for the average pilot I di at least an average job. Take it to cirrus center, speak to Duluth, get advice, and block the seat and tested it by pushing hard before take off. My plane does not have the warnings on the picture you showed. To me that means they KNOW there is a problem. I spoke with Ross in service today before the latest mishap. No mention of this bar. Exactly what is the procedure I am supposed to do? I appreciate the NTSNB report I just am feeling a little personal about it as I have done diligence and my life is personal. I will ground the plane or fly from right seat until certain it’s ok. Bummer Ross at Cirrus didn’t admit to this NTSB report…I asked if this had ever been an issue, time for a nasa report and a FISDO report, I am sure Cirrus monitors this so Ivey or whomever monitors you know how to contact the thanks…

1 Like
#14

Yes

#15

Bill Crawford,

So if I do the jiggle and push and pull and later it decides to fly back after taking it to a cirrus center and talking to Duluth it’s my fault…glad we don’t fly together.

#16

Thanks Brian for being constructive.

#17

Says the guy who can’t figure out how a seat works…

#18

Thanks Paul white…same experience now but both times I chose to rotate…

#19

Hmmmm…somebody needs a day job.

#20

This almost needs to be a checklist item. Incredibly dangerous. I’m thankful it’s never happened to me.

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