Horstroad
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How Safe Are Jumpseats?

Mon Dec 31, 2012 1:09 pm

I'm talking about the 737 first observer seat in particular.
I really can't imagine how this rattly folding chair can withstand any harder impact, especially with the backrest (which holds the seat belt) just clipped into those little brackets in the doorway. in addition on some of them you sit right on the housing of the retractable seat belt with your tailbone, which isn't only uncomfortable but also a possible cause of injuries during a hard landing or an accident.

on the ERJ190 the part of the seat belt that goes between your legs is nonexistent, so the buckle tends to move towards your stomach, which I think doesn't help much during an accident.


despite those concerns I wouldn't trade anything for this privilege of flying in the cockpit from time to time. I'm just interested what the rate or severity of injuries on these seats is compared to pilot seats, cabin jumpseats and pax seats.

[Edited 2012-12-31 06:03:29]
 
tdscanuck
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RE: How Safe Are Jumpseats?

Mon Dec 31, 2012 6:37 pm

Quoting horstroad (Thread starter):
I really can't imagine how this rattly folding chair can withstand any harder impact, especially with the backrest (which holds the seat belt) just clipped into those little brackets in the doorway.

They're still rated to full crash loading (among other things, they don't want the jump seat passenger flying forward and taking out the pilots or control panels). They're just not comfortable. A big reason that the jumpseats can be so flimsy relative to the pilot seats is that the jump seats aren't adjustable...it's way easier to make strong joints if you don't also have to be able to relocate them.

Quoting horstroad (Thread starter):
in addition on some of them you sit right on the housing of the retractable seat belt with your tailbone, which isn't only uncomfortable but also a possible cause of injuries during a hard landing or an accident.

As long as it won't kill you and won't structurally fail, I think they consider it good. Comfort isn't a factor, especially for the 737 jumpseats. Just be glad you're in the first observer seat and not the second.

Tom.
 
FI642
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RE: How Safe Are Jumpseats?

Mon Dec 31, 2012 6:39 pm

Several years ago I was involved with hard landing - several jumpseats were torn from the bulkhead they were
attached to. Two of my friends (flight attendants) were injured. Neither were able to return to work.
737MAX, Cool Planes for the Worlds Coolest Airline.
 
roseflyer
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RE: How Safe Are Jumpseats?

Mon Dec 31, 2012 7:46 pm

Like all seats on newly delivered airplanes they can support the weight of the 95th percentile adult male in a 16 G impact.
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Tod
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RE: How Safe Are Jumpseats?

Tue Jan 01, 2013 3:45 pm

Quoting Roseflyer (Reply 3):
Like all seats on newly delivered airplanes they can support the weight of the 95th percentile adult male in a 16 G impact.

170lb x 16g.

See 14CFR25.562 for that and some of the other requirments.

http://www.ecfr.gov/cgi-bin/text-idx...ode=14:1.0.1.3.11.3.169.63&idno=14
 
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zeke
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RE: How Safe Are Jumpseats?

Tue Jan 01, 2013 4:31 pm

Quoting Roseflyer (Reply 3):
Like all seats on newly delivered airplanes they can support the weight of the 95th percentile adult male in a 16 G impact.

I can understand that requirement for new passenger seats, as many aircraft are basically certified as "green". However I do not think that would apply to jump/crew seats, I would have thought they would be part of the original certification basis.
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roseflyer
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RE: How Safe Are Jumpseats?

Tue Jan 01, 2013 6:55 pm

Quoting zeke (Reply 5):
Quoting Roseflyer (Reply 3):
Like all seats on newly delivered airplanes they can support the weight of the 95th percentile adult male in a 16 G impact.

I can understand that requirement for new passenger seats, as many aircraft are basically certified as "green". However I do not think that would apply to jump/crew seats, I would have thought they would be part of the original certification basis.

Grandfathering usually is not acceptable for newly delivered airplane interiors. There are many certified to 9 Gs in service but all new airplane interiors ( floors, seats, galleys, etc) must meet the latest requirements. Interior certification is a bit different than the airframe which has much more grandfathering and doesn't have the same scrutiny on each airplane.
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zeke
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RE: How Safe Are Jumpseats?

Tue Jan 01, 2013 11:11 pm

Quoting Roseflyer (Reply 6):

Grandfathering usually is not acceptable for newly delivered airplane interiors. There are many certified to 9 Gs in service but all new airplane interiors ( floors, seats, galleys, etc) must meet the latest requirements. Interior certification is a bit different than the airframe which has much more grandfathering and doesn't have the same scrutiny on each airplane.

Yes, however you missed the point, where do you think jump seats exist ? Cargo and passenger aircraft have jumpseats in the same location. Looking at the OP, they are referring to the observer seats in the cockpit that are there regardless of what is behind the cockpit door. Those seats I would think are part of the original aircraft configuration/certification, like the other cockpit seats.

I fully understand regarding a new interior for a passenger seat, as that is basically a modification, the cockpit would remain unchanged.
We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
 
Tod
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RE: How Safe Are Jumpseats?

Wed Jan 02, 2013 12:10 am

The OEM delivered configuration certification basis is defined in the type certificate data sheet.

http://www.airweb.faa.gov/Regulatory...keModel.nsf/MainFrame?OpenFrameSet
 
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TZTriStar500
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RE: How Safe Are Jumpseats?

Wed Jan 02, 2013 1:27 am

Quoting zeke (Reply 5):
I can understand that requirement for new passenger seats, as many aircraft are basically certified as "green". However I do not think that would apply to jump/crew seats, I would have thought they would be part of the original certification basis.

Yes, it does apply and both crew and passenger seats meet TSO requirements and 14 CFR 25.785. In the late 90's there was a move away from TSO-C39 (9g) to TSO-C127 (16g). The manufacturers started to make seats to 16g and now most meet this requirement though 14 CFR 25 did not require it until almost 10 years later. During that time, the FAA forced replacement of 9g seats with 16g only in cases where the interior was 'significantly' changed. New aircraft must now meet 14 CFR 25.562 (16g dynamic testing) as alluded to by Tod. Also in the US, aircraft operated under 14 CFR 121 must meet this if manufactured after October 27, 2009. After that date, all of the manufacturers switched to delivering aircraft with 16g passenger AND crew seats. However, aircraft built before that are grandfathered. Through attrition they are retired or when reconfigured, new 16g seats are installed as that is the latest standard for any new seats.

Quoting Roseflyer (Reply 6):
Grandfathering usually is not acceptable for newly delivered airplane interiors. There are many certified to 9 Gs in service but all new airplane interiors ( floors, seats, galleys, etc) must meet the latest requirements. Interior certification is a bit different than the airframe which has much more grandfathering and doesn't have the same scrutiny on each airplane.

This is not true for older aircraft. The original certification basis remains valid for each aircraft type if an older aircraft is reconfigured or retrofitted. Seats and monuments are built to the latest strength and flammability requirements, but the aircraft may not be nor have to be. AC 21.101-1A explains establishing the certification basis for changed products.
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highflyer9790
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RE: How Safe Are Jumpseats?

Wed Jan 02, 2013 4:16 am

safe enough to get me to work and to get me home.
121
 
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HAWK21M
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RE: How Safe Are Jumpseats?

Wed Jan 02, 2013 9:49 am

Quoting horstroad (Thread starter):
on the ERJ190 the part of the seat belt that goes between your legs

Termed the "crouch strap".

Quoting tdscanuck (Reply 1):
Just be glad you're in the first observer seat and not the second.

Ezactly my thought esp for the B737 ..... 
Quoting FI642 (Reply 2):
Several years ago I was involved with hard landing - several jumpseats were torn from the bulkhead

Any details......
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Fabo
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RE: How Safe Are Jumpseats?

Thu Jan 03, 2013 12:27 am

Quoting tdscanuck (Reply 1):
Just be glad you're in the first observer seat and not the second.

  

I almost fell on the circuit breaker panel when that seat was first shown to me. I had no idea there could be one crammed there. And the poor soul meant to fly to Turkey and back to Slovakia on it, IIRC, to position home.
The light at the end of tunnel turn out to be a lighted sing saying NO EXIT
 
tdscanuck
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RE: How Safe Are Jumpseats?

Thu Jan 03, 2013 12:53 am

Quoting zeke (Reply 7):
Yes, however you missed the point, where do you think jump seats exist ?

It's in the interior. Flight deck is not exempt from interior certification requirements. *If* they roll the cert basis for the interior (which they usually do) then it applies to the flight deck too, including the observer seat(s).

Quoting Fabo (Reply 12):
I almost fell on the circuit breaker panel when that seat was first shown to me. I had no idea there could be one crammed there.

It really isn't a seat...I've gotten into arguments with flight crew who swore that they didn't have the 2nd observer seat (it's an option on some aircraft) and I had the drawings and configuration documents saying they did...turned out they had it, they just never realized it was a seat.

Tom.
 
Fabo
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RE: How Safe Are Jumpseats?

Thu Jan 03, 2013 5:08 am

Quoting tdscanuck (Reply 13):
(it's an option on some aircraft)

yep. something something 213B33 it used to be on the 737NG, not sure if still is.

Quoting tdscanuck (Reply 13):
.turned out they had it, they just never realized it was a seat.

I certainly dont blame them for that!
The light at the end of tunnel turn out to be a lighted sing saying NO EXIT
 
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zeke
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RE: How Safe Are Jumpseats?

Thu Jan 03, 2013 12:45 pm

Quoting tdscanuck (Reply 13):
It's in the interior. Flight deck is not exempt from interior certification requirements. *If* they roll the cert basis for the interior (which they usually do) then it applies to the flight deck too, including the observer seat(s).

"they" I assume you mean Boeing. It just seems strange to me, as the cockpit seats are about the only seats which remain consistent regardless of what is behind the door. That being said, I do not know enough about what is behind the rules regarding these 16g seats, I would need to have a good look at the loads they are actually looking at, it maybe seats that have been installed since day 1 may in fact meet the 16g requirements, it is a simple matter of testing to expand the "envelope" for the seat.

I do not seem to recall any difference in what I sit on over the years, regardless of the number of changes behind the doors.
We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
 
Tod
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RE: How Safe Are Jumpseats?

Thu Jan 03, 2013 3:20 pm

Quoting zeke (Reply 15):
"they" I assume you mean Boeing

Typically when an aircraft is reconfigured the cert basis is part of the STC cert plan submitted by the integrator to the FAA for their approval.

I don't recall any recent major interior reconfiguration cert plans where I work where the cert basis for the flight deck seating was changed from that of the pre-mod configuration.
 
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bikerthai
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RE: How Safe Are Jumpseats?

Thu Jan 03, 2013 8:55 pm

Are the 1st and 2nd Observer Seat are considered jump seats exclusively?

Or are the flight attendance seats considered jump seats also?

I beleive that 9G is a 9G static where as the 16G is a 16G dynamic. The loading is not linearly scalable.

bt
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737tdi
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RE: How Safe Are Jumpseats?

Thu Jan 03, 2013 9:10 pm

Quoting tdscanuck (Reply 13):
It really isn't a seat...I've gotten into arguments with flight crew who swore that they didn't have the 2nd observer seat (it's an option on some aircraft) and I had the drawings and configuration documents saying they did...turned out they had it, they just never realized it was a seat.

Tom




As a height impaired (short) person I usually have the pleasure, although by my choice, of "relaxing" on the 2nd observers seat when flying to or back from repair of our aircraft. Don't know how a flight crew wouldn't know that it is a seat, it has a shoulder and lap harness. We call this seat the "tombstone" due to its like sitting on a marble slab.
 
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zeke
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RE: How Safe Are Jumpseats?

Thu Jan 03, 2013 9:49 pm

Quoting Tod (Reply 16):


I don't recall any recent major interior reconfiguration cert plans where I work where the cert basis for the flight deck seating was changed from that of the pre-mod configuration.

Neither do I, the only changes I see in the cockpit seat from time to time is the replacement of the seat covers or seat belts due to wear. I have not noticed any difference with the cockpit or cabin crew seating after an interior upgrade. Mind you where I work we are outside FAA land, and basically follow EU OPS.

I know after picking up aircraft following a cabin upgrade the cockpit/crew seats were in the same state they were prior to the shop visit.
We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
 
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neutrino
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RE: How Safe Are Jumpseats?

Fri Jan 04, 2013 2:59 pm

Quoting tdscanuck (Reply 13):
It really isn't a seat...I've gotten into arguments with flight crew who swore that they didn't have the 2nd observer seat (it's an option on some aircraft) and I had the drawings and configuration documents saying they did...turned out they had it, they just never realized it was a seat.

Oh, this info has come to me 16 years too late.
There were two of us traveling on a Silkair 737 from Sin to Jkt and the captain happened to be someone we know. He invited one of us to occupy THE jumpseat. If I had known there is a second one, I would have pointed it out to the captain (assuming the aircraft had one fitted and he didn't know of it) and would have a great experience regardless of how uncomfortable the seat might be.
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atct
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RE: How Safe Are Jumpseats?

Fri Jan 04, 2013 6:10 pm

The 737 has the option of a second cockpit jumpseat, just not all carriers have it. United (Continental) does not have it but Alaska does. I have never had the "pleasure" of riding on the straddling chair but it looks tight. Ive ridden on the main 737 jumpseat and its not bad as far as jumpseats go. Plenty of room (im 5'8) and very sturdy once you get it into position. The 757 hanging chair is by far the worst.

atct
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Tod
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RE: How Safe Are Jumpseats?

Fri Jan 04, 2013 6:19 pm

Quoting atct (Reply 21):
The 757 hanging chair is by far the worst.

Just wait until you see the MRJ jump seat.

Its located right in front of the flight deck door.
Mounted to the bulkhead and swings out of the way to use the door.
Feet and knees right up against the center console.
Any time someone wants to use the door, you must get up and stow the seat, but where do you stand while doing that?
Can it even be done if you are of above average size?
That was TBD when I left the program two years ago.
Should be a hoot.
 
yeelep
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RE: How Safe Are Jumpseats?

Fri Jan 04, 2013 6:46 pm

Quoting Tod (Reply 22):

You pretty much described the 737 first observer seat.

For those not familiar with the 737 observer seats:
Big version: Width: 640 Height: 480 File size: 117kb

edit to add picture.

[Edited 2013-01-04 11:13:23]
 
Tod
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RE: How Safe Are Jumpseats?

Sat Jan 05, 2013 5:05 am

Quoting yeelep (Reply 23):
You pretty much described the 737 first observer seat.

Snug, but roomy compared to the MRJ prototype configuration.
 
Horstroad
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RE: How Safe Are Jumpseats?

Sat Jan 05, 2013 11:31 am

Quoting yeelep (Reply 23):

looks unlatched... this jumpseat is probably not as safe as it could be 
 
737tdi
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RE: How Safe Are Jumpseats?

Mon Jan 07, 2013 5:43 am

Quoting horstroad (Reply 25):
looks unlatched... this jumpseat is probably not as safe as it could be

Hey, it is the pointy end. It really does not matter. LOL.
 
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HAWK21M
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RE: How Safe Are Jumpseats?

Thu Jan 10, 2013 6:53 am

Quoting Tod (Reply 22):
Just wait until you see the MRJ jump seat.

Any pictures.....
I may not win often, but I damn well never lose!!! ;)

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