Pilot's seating choices - a new consideration

[Battson]

I had a chance to pilot a new B model Bearhawk recently, and noticed a difference between the seats and the view which I thought it worth sharing. There were two different ways of doing it - each with different benefits.

In our 4-place, we have a seat pan with soft foam and webbing straps, which allows the pilot to sink down into the seat a little way, perhaps 2 or 3 inches.


In the Bravo I flew (noting the different wing profile), they had thicker and firmer foam with a solid seat pan - aluminum I think. So the seating position was higher to start with, and there was very little sink into the foam. Overall, the seating position was at least 4" higher.

I noted some differences in the piloting experience.
- With the lower seating position, over the nose visibility was slightly reduced, but I could see under the wing and also put my head out the window to see what I am taxiing over in an off-airport situation.
- With the higher seating position, forward visibility was fractionally better (not a lot - tire size is the main factor), but I could not see the underside of the wing - when I looked left all I could see was wing root and fuel gauge about 6" in front of my face. I could not crane my neck low enough to get my head out the window. This changed the feel of the plane, making it a little more enclosed. My head was also very close to the structural tubing (skylight, no headliner) and the headset was touching the overhead cross-bars when we hit turbulence.

[AKKen07]

That is a very interesting observation. I am just about to undertake a headroom improvement mod in my plane to keep my head from the crossbars. If I could get 2 plus inches with just a seat webbing change it would save me a project!

[Nev]

Very interesting.

Ive already installed aluminium seat pans, and shortly to go to the upholsterer. Has anyone used aluminium pans with thinner foam, with good results ?

[spinningwrench]

I made a custom molded carbon fiber pan with a dish in both the bottom and the back. Oregon Aero will be upholstering with their 1" foam which is their recommended minimum. In my Patrol I still end up with great head room and being 6'4" that is something I thought about a lot. The overhead opening with the skylight might however be better than the 4 place.

[whee]

Good points of observation Battson. Thanks for sharing.

A couple of thoughts. The B wing is thinker and I think someone said the bottom of the wing is 1” lower than the A wings. That would also play a part in what we are talking about here.

Basically all my flight time is in a Luscombe and in those airplanes your head is up in the root. You have to hunch over to see out the side windows. As Battson described it makes the airplane feel more enclosed. I did not want that feeling and I wanted my head as far as possible from the overhead tubes. To accomplish this I covered my seat frames in heavy fabric and only shrunk it enough that I could not feel the seat frame with my legs when sitting on the seat. We used minimal foam, I can’t remember exactly but I think it’s 1.5” and I’m able to sit in the seat for hours comfortably.

When I started flying the airplane I felt like I was in a fishbowl; the visibility is awesome.

[Pbruce]

I tried that and found that the slack fabric was very difficult to shrink evenly. Still, I now have a layer of heavy fabric laid down (a bit lumpily) on my front
seat with enough slack to depress to about half of the frame tubing diameter. That is not buying me a lot of headroom.(3/8" maybe) Im now considering ripping it off and applying the fabric taught to the bottom of the seat frame. That way, I can fill the full tubing depth with firm foam, and then add medium and soft layers on top of the firm foam and frame. Anything I should watch for? what am I not seeing?

[Nev]

Well I decided to get scientific (and make some aeroplane noise) as I’ll be getting my seats upholstered soon.

I’ve cut some 40mm (1.5 inch) thick foam for the seat pan and back. With the seat position forward my son was too tall to see under the window frame. For myself, I was just able to see under the frame.

My door has about 1/2” lower skin all around to capture the acrylic, so for those who are screwing the acrylic straight to the steel frame , you can gain a small advantage.

Definitely I couldn’t do 4 inch seat squabs, even 2 inches would be marginal for me to retain the ability to see under the wing, so this is something I’ll have to decide. I’m thinking at this stage to increase the thickness towards the front of the seat, and keep it around 1 1/2 inches at the back where the weight will be, something to discuss with the upholsterer.

Comments appreciated.

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[Battson]

I would advocate for thicker seat squabs at the front edge of the seat. Especially for taller people. You'll tend to fly with the seat rolled forward, which means you need more support for the front of your legs, to prevent the seat of your pants from getting sore...

[Hewko]

I had a similar experience on my Murphy Rebel. After flying for a couple years, I added more foam to be comfortable for hrs, then found the vision under the wing was limited unless I ducked my head down. So I cut the seat legs down to regain the under wing visibility, I found that to be much more comfortable and safer. I also added a higher seat back on my Rebel for head support on long trips, and I will definitely be doing the same on my bearhawk.

[Mark Goldberg]

This is one of those areas where we all make our planes to meet our preferences. Aluminum seat bottoms and taunt heat shrunk fabric do not deflect much downward. Which is totally OK if you are not 6'6" or very tall. Webbing is good if you are tall and do not want your head too high. I generally prefer to have my head up high as it makes me "see" the situation better when landing and taking off. I read a Dick VanGrunsvens article where he recommended getting your head up high in a tailwheel plane to see better for take offs and landings. I found myself agreeing with him.

Again, we all are not the same with the same preferences. Mark

[Utah-Jay]

I am 6’2” and I like to sit on a 1.5” pad on top of the seat for superior visibility on the ground. Majority of the time I am looking out the front window in the air, of course I duck my head to make turns or look up through the “skylight”

Edited to add: Rans S-21

[Bcone1381]

Consider your cushion thickness and firmness.

https://www.sunmatecushions.com/coll...pedic-cushions

This is a link to the supplier I used for my memory foam seat cushions. They manufacture it in various firmnesses (is that a word?) I tested different firmnesses and layering by sitting for hours on them. I looked for any pain. Lower back pain after sitting a long time is the common issue for me.

Their Soft and Medium soft product caused lower back pain, even with lumbar support. However, 1 inch thick Medium on top of a fabric base was comfortable even after two hours. The seat back had lumbar support, the seat bottom was flat. I'm 160 pounds. I found firmer moved the comfort up. I did not try but would like to try Medium-firm. (​​​​​and ​it looks like There Sunmate FRG product passes the FAA burn test. Also check out there discount overstocks.)

So in my experiment an inch thick foam cushion will work just fine, just lean to the firm side. I would not think a "Joann Fabric" foam product to work well, but I did not test it.

[N8doggaf]

Does anyone have our know if a visual documentation of building up their seat cushions? I'm having a rough time figuring out even relative dimensions for inner and outer bounds to stay within. I've read Tony B's Construction Techniques and the kit plane articles. They're informative on basic principles on how to make it your own. But my pea brain needs a place to start from. What are things folks have done to the cushion shape to account for the folding backrest?

[svyolo]

I don't have any experience making a comfortable seat, so I am going with a $20 dollar pair of Costco seat covers for upholstery, and I will play with the foam till I get it right. After I am satisfied with the result, I will pay someone to upholster them. Or maybe not :<).

[jaredyates]

Does anyone have our know if a visual documentation of building up their seat cushions? I'm having a rough time figuring out even relative dimensions for inner and outer bounds to stay within. I've read Tony B's Construction Techniques and the kit plane articles. They're informative on basic principles on how to make it your own. But my pea brain needs a place to start from. What are things folks have done to the cushion shape to account for the folding backrest?

I didn't worry about the back seat folding when designing the cushions. We made the bottom seat cushion extend from the backrest forward, and then set the back rest cushion on top of that (up 2" in our case). In operation, when we press forward on the seat back, it will still fold forward, mushing the foam as necessary.

[davzLSA]

Does anyone know of anyone else that has bought ready made racing seats from one of the speed shops? If they could be found light enough that might save lots of time and head scratching?

[Bissetg]

Interesting and useful information, thanks Jono.

I’m a sniff under 6’4. Definitely worth putting the time into getting this right as a good lookout is safety critical.

My B model with the alloy bottomed seat with 1 inch foam, in the full aft position just gives me good vis under the wing (still under build in the shed so the views not a great one) and satisfactory head clearance. I have foam lagged the X members just in case though.