Forward Visibility
Posted: Sun Jun 25, 2017 2:24 pm
by Paul Johnson
I have just purchased a flying Sonex 3300 tri gear so I have something to fly whilst I build my Sonex B, I only have the tail kit at the moment and have not started it due to other commitments. The main reason for purchasing a flying aircraft was that I had sold my present aircraft and thought it would scratch the itch one way or the other in my pursuit of a Sonex which I have admired since 2007 when I had completed my RV 8. The itch is scratched but for the forward visibility especially during landing, I have a lot of glare reflecting in the windshield, the combing is dull so should not impact that much, the main problem is that the windshield just seems difficult to see through and has a detrimental effect on depth perception. I can not think this to be normal as I have to use peripheral vision to land, if anybody has any suggestion I would gladly like to hear.
Re: Forward Visibility
Posted: Sun Jun 25, 2017 9:34 pm
by rbarber
What is the glare shield covered with? A black non reflective cloth is the usual fix. Just a guess at the issue…
R.
N157SX (Sexy Hexy)
Re: Forward Visibility
Posted: Sun Jun 25, 2017 11:11 pm
by kevinh
Hi Paul,
Glad to have another fellow former RV builder here. I bet you’ll have a great time, I’m digging my waiex build.
Re: Forward Visibility
Posted: Mon Jun 26, 2017 4:31 am
by Paul Johnson
Thank you for the replies, my first plan of action is to clean and polish the windshield, the glare shield is covered in a grey type material that matches the side panels, the aircraft is fitted with a Sonex interior not the newer nylon but more of a velour. I do sit quite high in the aircraft as it does not have the lower seat mod, could it be that I am just looking through more lexan than I should or would this not make a difference.
My best description of the view through the windshield is that of a poor quality movie.
The RV8 is hard to beat but the Sonex is a real sporty aircraft to fly.
Re: Forward Visibility
Posted: Mon Jun 26, 2017 5:00 am
by peter anson
Hi Paul, yes the forward visibility is that bad. At my home airfield the sealed runway is very narrow and nearly disappears just before touchdown. I can usually get a glimpse of it by jamming my head as high and far to the left as I can. I can live with it unless there is a low sun causing extra glare, and it doesn’t have to be directly in front either. I have now done over 560 landings so it can’t be that bad, but to my mind it is a major flaw in the design. There was some discussion on another post about the difficulty of getting the correct tint polycarbonate in Australia for making a replacement windshield, but if I do replace the windshield I will be using clear poly in the hope of improving forward visibility.
Peter
Sonex 894
324 hours
Re: Forward Visibility
Posted: Mon Jun 26, 2017 5:30 am
by Paul Johnson
Peter,
Thank’s for the input, I believe your aircraft has a tail wheel, mine is a of the nose wheel variety so I do not lose the runway on landing, I have difficulty in all phases of flight but more so on the landing or descending with terrain in the windshield were clarity through the perspex canopy is far superior.
Re: Forward Visibility
Posted: Mon Jun 26, 2017 8:57 am
by builderflyer
Paul,
That Sonex supplied glareshield material has a bit of sheen to it that makes it unacceptable for its intended purpose. I sprayed mine with a flat black cloth paint and that made a world of difference. Also, if not already done, spray the exposed part of the back of the upper firewall with flat black paint. You’ll be happy with the improved visibility out front once both of these items are done.
Art,Sonex taildragger #95,Jab3300 #261
Re: Forward Visibility
Posted: Mon Jun 26, 2017 11:04 am
by peter anson
Hi Paul, I agree with Art’s advice, especially about painting the exposed parts of the firewall.
Part of your problem might just be the different perspective from flying an RV. I took control in a friend’s RV6 a while back and found that I was tending to climb all the time because I wasn’t used to being able to see so far below the horizon.
For what it’s worth, when my Sonex is in straight and level flight, the horizon appears “2 or 3 inches” above the top of the firewall. I don’t know how to describe that better, but the horizon appears about halfway up the fuel vent tube ( I have the top vent). I have only flown in one other Sonex and that was several years ago so I don’t know if that is the usual view. Anyone else??? If you can’t see that much I guess it would indicate that the wings are rigged a little flatter than mine. Even though I can see a little below the horizon, a bit of distortion in the dark windshield makes the view fairly indistinct.
Peter
Re: Forward Visibility
Posted: Mon Jun 26, 2017 11:25 am
by Fastcapy
My opinion is that it is due to the amount of slope on the windshield as you are looking through that much more material. Now add the tint to the mix and you have a design that gives poor forward visibility.
I have issues picking out traffic in the pattern that is directly in front of me through the windshield, to the point where I will put it in a quick slip or small s-turn so I can see out canopy instead of the windshield. I can then normally pick out traffic through the canopy whereas I can’t see them through the windshield.
I also do a lot of slips on final especially at dusk and night to give me a better sight picture of the runway.
Re: Forward Visibility
Posted: Mon Jun 26, 2017 1:48 pm
by Paul Johnson
Mike,
What you describe is identical to my situation. Art the forward corners of the firewall have not been painted so I will give that a try.
Re: Forward Visibility
Posted: Mon Jun 26, 2017 3:00 pm
by radfordc
peter anson wrote:I have now done over 560 landings so it can’t be that bad, but to my mind it is a major flaw in the design.
That “design flaw” may be why you can go 130 mph with a VW engine.
Re: Forward Visibility
Posted: Mon Jun 26, 2017 4:15 pm
by Paul Johnson
Good Point.
Re: Forward Visibility
Posted: Tue Jun 27, 2017 1:22 am
by peter anson
radfordc wrote:That “design flaw” may be why you can go 130 mph with a VW engine.
I doubt if the long tapered windshield improves the aerodynamics that much. If it was that effective we could reduce the drag on wheel pants by putting long tapered points on the front and even reduce wing drag by having longer tapered leading edges. You obviously don’t want a jeep windshield but what seems to work best for low drag is a teardrop shape, and there are practical considerations, like being able to see where you are going.
Peter
Re: Forward Visibility
Posted: Tue Jun 27, 2017 1:40 am
by rizzz
peter anson wrote:
radfordc wrote:That “design flaw” may be why you can go 130 mph with a VW engine.
I doubt if the long tapered windshield improves the aerodynamics that much. If it was that effective we could reduce the drag on wheel pants by putting long tapered points on the front and even reduce wing drag by having longer tapered leading edges. You obviously don’t want a jeep windshield but what seems to work best for low drag is a teardrop shape, and there are practical considerations, like being able to see where you are going.
Peter
I think John Monnett actually confirms this in the B model presentation.
He is asked if the B-model would produce more drag given the shape of the fuselage is less “pointy” now (not sure what the actual word was that was used in the question).
John answered that because the width at the widest point hasn’t changed it’s irrelevant (again he used different wording which I cannot remember correctly).
Re: Forward Visibility
Posted: Tue Jun 27, 2017 5:00 am
by Paul Johnson
I do not want this thread to go negative as the Sonex is a very sporty aircraft and compares highly with the RV in that role. In the original post I said that I had acquired this aircraft so I could evaluate the Sonex in depth whilst I was building the B model. I have sat in the B model and found it to be a good fit but at that time I had relatively no experience of the forward visibility of Sonex, so I was not looking at the aircraft from that aspect. I have noticed from video’s that it appears the seat is much lower in the B model and some of the video shots through the windshield are of an acceptable forward view. The aircraft that I have does not have the lower seat mod so I do sit about as high as one could without being restricted by the canopy,
Re: Forward Visibility
Posted: Tue Jun 27, 2017 6:55 pm
by mike.smith
peter anson wrote:Hi Paul, I agree with Art’s advice, especially about painting the exposed parts of the firewall.
Ditto. I have a nearly flat black fabric on my glare shield, and flat black paint on the forward part of the firewall that extends above the glare shield (one of the best decisions I made early on).
https://www.youtube.com/watch?v=OP_xN9Vdp8w
I don’t find the front wind screen to be an issue, even the times I’ve done a little flying at night. It’s really the length of the nose; psychologically I’m always straining to look over the nose. Nothing you can do about that. I just remember that a P-51 suffers from the same thing, so good heritage. 
Re: Forward Visibility
Posted: Tue Jun 27, 2017 7:12 pm
by Corby202
The windshield does distort the forward view a little but I have not found it to be a problem.
The bigger problem is getting the correct covering on the glare shield and upper firewall. I covered mine initially with lightweight carpet which I thought would not reflect anything. At certain Sun positions it reflected badly around the firewall area, it was very noticeable from video if I had a camera along. After trying different types of material, the fabric that worked the best was a black felt type of material sold on EBAY as a speaker box lining.
Re: Forward Visibility
Posted: Wed Jun 28, 2017 4:53 am
by Paul Johnson
I have a friend who used to own a company that manufactured speakers, he has rolls of the fabric so I will give it a go. As I did not build this Sonex is it just a case of removing the screws and the wind screen will come out so as to make it easier to install the fabric and apply the paint? The other thing I have noticed is that the wind shield is of a darker tint than the canopy, I have searched through the internet for images some seem darker and some don’t but I guess this could be just the light.
Re: Forward Visibility
Posted: Wed Jun 28, 2017 8:27 am
by DCASonex
Plain black felt from local fabric shop. Held in place with the hook side of 3/4" wide adhesive backed Velcro applied to perimeter of glare shield and up along upper curved arc of firewall. Let sides of felt sick up enough to cover nuts at bottom edge of windshield. Quick, easy, removable, and effective eliminating glare.
David A. Sonex TD