Seat Structure Questions

For general discussion of the Just Aircraft family of aircraft.
Includes: Highlander, Escapade, Summit and SuperSTOL.

Moderator: scubarider2

Seat Structure Questions

Postby Wes » Thu Jun 12, 2008 9:09 pm

To try to answer some questions (off line) about the Highlander seat structure, I have uploaded some pics of my seats.
The bottom photo has arrows to point out the bracing of the primary fore&aft seat rails. These rails support the majority of the passenger weight and are very substantial square steel stock that is welded at the fore and aft attach points and braced as shown.
The middle photo shows the adjustable seat temporarily raised to show the heavy walled aluminum adjustment tube that primarily secures the seat in the fore/aft direction and supports a fraction of the seat load. The sliding portion of the seat is reinforced to provide a "hammock" effect of steel tube for energy absorbtion in the event of a severe impact. Notice the angled steel brace on the seat adjust tube (unattached) that will provide vertical and lateral support of the mid-point on the adjust tube.
The top pic shows the seat in position on the rails with the UMDH plastic runners that allow for a low friction, easy adjustment of the loaded seat. The seat adjust 'T' locking pin is shown at the leading edge of the movable seat frame and provides a simple, foolproof and strong seat lock mechanism.
The one area of weakness may be the seat back that can be damaged if heavily mis-loaded. I noticed that without the cushions installed and seat back folded flat, a load imposed on the folded seat back will tend to deform the seatback tubes where they contact the hinge structure. I discovered this after doing something stupid like crawling into the baggage area to check a battery mount after I had removed the seat cushions and folded the seat backs flat.
All-in-all the seat structure is a robust and clever design that should provide the strongest and most effective seat construction of any of the light sport aircraft.

Hope this helps,

Wes

Wes
Attachments
SeatStructure3.jpg
SeatStructure3.jpg (47.76 KiB) Viewed 1373 times
SeatStructure2.jpg
SeatStructure2.jpg (39.32 KiB) Viewed 1373 times
SeatStructure1.jpg
SeatStructure1.jpg (46.98 KiB) Viewed 1373 times
Kit # 95
Low and Slow - The only way to go!
User avatar
Wes
Premium Member
 
Posts: 231
Joined: Mon Jan 23, 2006 10:32 pm
Location: Satellite Bch, Florida

Postby Dave Krall CFII SEL SES » Fri Jun 13, 2008 12:11 am

We've taken the external braces off one seat, opened up the hinge area and added reinforcement tube to the seat back from inside the existing vertical seat back tubes. The seat back is adjustable in angle by chain links from nearly fully reclining (until it touches the airframe brace) to fully folded forward without cushions, which are removed and placed on top of the folded seats for the occasional sleepover.

Later I'll get to a pin system so they're quickly removeable for camp chairs but still strong.
Dave Krall CFII SEL SES
Veteran Member
 
Posts: 922
Joined: Wed Mar 14, 2007 11:29 pm
Location: Seattle WA

Seat Backs

Postby Wes » Fri Jun 13, 2008 7:20 am

Dave,
Sounds like you have really improved the seat back situation.
When you get time, post some pics of your mods. I may want to plagerize.

Thanks,
Kit # 95
Low and Slow - The only way to go!
User avatar
Wes
Premium Member
 
Posts: 231
Joined: Mon Jan 23, 2006 10:32 pm
Location: Satellite Bch, Florida

Re: Seat Backs

Postby Dave Krall CFII SEL SES » Fri Jun 13, 2008 9:51 am

Wes wrote:Dave,
Sounds like you have really improved the seat back situation.
When you get time, post some pics of your mods. I may want to plagerize.

Thanks,


The chain adjust system falls into the "I don't like the way it looks" category for most pilots however, when I see what it will do for the weight & cost, it looks a lot better than something standard that really doesn't do anything good except sit you bolt upright...
Dave Krall CFII SEL SES
Veteran Member
 
Posts: 922
Joined: Wed Mar 14, 2007 11:29 pm
Location: Seattle WA


Return to Just Aircraft

cron