Chris Foss Phase 5 & 6 - RC Groups
Thread Tools
Nov 28, 2017, 09:00 AM
Registered User
Discussion

Chris Foss Phase 5 & 6


Hello,

I'm interested in the Chris Foss Phase 5 and Phase 6 Sport, the Phase 5 would be built form plans and the Phase 6 is available as a kit, but what I've not been able to find yet is a comparison on how they perform.

If anyone's flown both I'd be interested to know your thoughts and if one has the edge over the other.

Many thanks, B
Sign up now
to remove ads between posts
Nov 28, 2017, 10:54 AM
Registered User
prodjx's Avatar
The P-5 has legendary status. I made my root airfoil with the new E-374 airfoil, haven't flown it as yet.
Nov 28, 2017, 11:50 AM
Registered User
Hi prodjx,

I assume you're still going for a symmetrical aerofoil at the tips? Do you happen to know what the original aerofoil profiles were for the Phase 5.

It will be interesting to know how the E-374 airfoil performs.
Nov 28, 2017, 12:15 PM
aka : SteveBB..
Stevepilot's Avatar
I have built and flown both. If you're interested I have build logs on both, the P6 on here.

https://www.rcgroups.com/forums/show...s-Foss-Phase-6

There is a discussion about the P6 V P5 and 'Enginetorque' makes interesting comments, including mentioning his friend who has built several P5s with different wing sections, etc but nothing improves on the original.

The P5 as you mentioned is from plans. It is a fine glider and I found a satisfying build. You'll need to jig it though to get the wing/aileron/flap correct. It isn't difficult, you just need to be methodical.
The P6 is from a kit and is available with semi or fully symmetrical wing. I built the semi sym one and put four servos in the wing with top mounted horns for the flaps (As I did with the P5 too). There isn't as much room in the fuselage as there is with the P5 and the wing is foam cored. Neither of which is a concern really, but I'd sink sheer webs into the wing on the P6 to reinforce the area where the servo wells are.

Flyingwise, I would say the P5 is better. Now whether that's because I had more experience with both building and flying when I built the P5 is probably a significant factor, but I found it more satisfying. Neither will ever out perform a modern glass ship but that isn't why they're built.

Pictures are P5 and P6.
Last edited by Stevepilot; Nov 28, 2017 at 01:10 PM.
Nov 29, 2017, 03:15 AM
Registered User
Thanks Steve, great to have your thoughts, I sent a cheque off to Chris Foss yesterday for the Phase 5 plans, and judging by your comments I made the right move.

Could you post a link to your Phase 5 build log, your Phase 6 build log was a very interesting read.

Thanks, B
Nov 29, 2017, 10:42 AM
aka : SteveBB..
Stevepilot's Avatar
Quote:
Originally Posted by Barnaby01
Thanks Steve, great to have your thoughts, I sent a cheque off to Chris Foss yesterday for the Phase 5 plans, and judging by your comments I made the right move.

Could you post a link to your Phase 5 build log, your Phase 6 build log was a very interesting read.

Thanks, B
Here you are, ignore the comments about having the wing made elsewhere.

http://www.rcmf.co.uk/4um/constructi...ive-build-log/
Nov 30, 2017, 06:27 PM
aka : SteveBB..
Stevepilot's Avatar
I found my notes on the maiden of the P5; and later when I had it nicely trimmed.

__________________________________________________ __________________________________________

I was going to simply add this to the build log, but that's done with..well not entirely, but I'll get to that..

The weather wasn't ideal when I turned up at the slope this morning, but by the time things were sorted, the sky looked more promising; and proved to be one of the better days (Albeit the sun was in the wrong place (makes note to have it moved))

I had the glider chucked off by one of my flying pals as I had no idea if I'd got the incidence right; but to my surprise it wasn't that far out, or the l/r trim..in fact it just flew around, but I realised there wasn't enough down throw, and too much aileron throw...so landed it.. (makes note, take the crow brakes out of the programming, as it really doesn't need them!)

One or two alterations later and up she went again..better this time, much better.. Try a few aerobatics..Don't let it slow up, or it will drop one tip first..and spiral...but recovery is okay with airspeed. Proved to fly inverted wonderfully, will do that all day. Rolling proved that the ailerons had un equal throws (Up/Down)..landed it, evened that up, and added some ballast in the box in the midships... Now it really went!! Wind had picked up and it fair carved around the sky, inverted it was climbing, rolls superb, goes where you point it, crisp response, no lag at all...Mr Foss, you've designed another good un here.


....and flew back to the slope, across the face and the turbulence grabbed it and brought it straight down, midships first..five yards in front of me..Broken the fuselage all the way round under the wing saddle, burst the wing joiner plates off the fuselage top, broken the rudder closed loop tiller mount off the ballast box..

Dejected somewhat...

Brought it home, stripped the film in the area affected.. Glued back and front together and clamped it up. I'll leave it overnight and see if it's still straight.. I'll glue in some ply lining and possibly glass it.. So far it looks the only damage, the wing was undamaged.

What makes it worse is it was my own stupid fault, I knew it was turbulent, and likely to chuck it about close in (AUW is just over 4 1/2 Lbs)..On the bright side, I know it flies, and flies well. Sure, it can't be compared with a modern glass ship; I never expected it to, but for a six foot wooden model, it shifts quite well.

Repaired; easier than I anticipated.. Check over and went up t'slope this morning. Decided to ballast it before trying, and it went very well. C.G. has been finalised and brought back a little by taking out 25 g from the nose.. Now dives without wanting to pull up..much more neutral. Ailerons sorted, and rolls axially as nature intended. Lands quickly, but not being lardy the speed and height can be scrubbed off by spilling the air as it comes in..No drama. I can't yet get over how responsive it is, it's as if all the surfaces are connected directly to my thumbs.



You might find this useful. I did when I built my P5.

http://phase5build.blogspot.co.uk/
Last edited by Stevepilot; Nov 30, 2017 at 06:37 PM.
Dec 01, 2017, 02:55 AM
Registered User
Thanks Steve,

Painful to read about the hard landing, but very encouraging about the flying. I would love to have a fully moulded glider, but think I'll save that for when I have many more slope hours to my name, what I want is a capable, predictable, graceful looking glider that I can build, and inevitably repair!
The Phase 5 just seems to fit the bill perfectly.

Hopefully the plans will arrive soon.
Dec 06, 2017, 08:32 PM
aka : SteveBB..
Stevepilot's Avatar
Quote:
Originally Posted by Barnaby01
Thanks Steve,

Painful to read about the hard landing, but very encouraging about the flying. I would love to have a fully moulded glider, but think I'll save that for when I have many more slope hours to my name, what I want is a capable, predictable, graceful looking glider that I can build, and inevitably repair!
The Phase 5 just seems to fit the bill perfectly.

Hopefully the plans will arrive soon.
Have you built it yet?
Dec 07, 2017, 03:01 AM
Registered User
Hi Steve,

I'm still waiting for the plan to turn up!

But then, inevitably, there will be the "appreciation of the drawing" phase, followed by the balsa order, some agonising on whether to go with a built up or foam wing, and a few other 'I wonder if I should do this or that' and then, and only then, will I be fully prepared to start cutting out the formers

I'm nearly finished on a TopModels Begin' Acro electric glider, then I've got an old PSS hawk to build next, I got the kit free on condition I built it and flew it soon. Then there is a Classic Pattern plane to build to replace the Atlas I crashed and dearly miss but it would make sense to order the wood for this and the Phase 5 at the same time, and maybe even work on both at the same time. Either way I would like both models as soon as possible as I'm very excited by both.

All the best, B


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Question Chris Foss Phase 5 Plan Chris Jenkins Slope 2 Oct 01, 2017 05:01 PM
Discussion Chris foss phase 6 sport parts plan Andynrose Slope 0 Dec 07, 2013 07:40 AM
Build Log Chris Foss Phase 6 build log Gary Binnie Slope 139 Nov 07, 2011 11:25 AM
Question Chris Foss Phase 6 COG nemo_uk Slope 2 Aug 10, 2007 10:06 AM