Seagull Hurricane Laser

[Tim Flyer]

Cheers Jon Please do. I’m sure the weather will improve soon. I expect to have mine sorted in a couple of weeks now.

Edited By Tim Flyer on 11/06/2019 15:59:26

[Tim Flyer]

All repaired now 😊

[ASH.]

She looks beautiful.. Well done Tim!

If there's any pics of the repair please put them up.

[Tim Flyer]

Cheers Ash I’m afraid I didn’t take pics as I went along.

The most critical and tricky bit was joining the two halves of the fuselage. One side was almost intact but there was a fair bit of damage to the wing seating on both sides. For the initial join I mounted the front half of the fuselage on a strong heavy wooden batten on my bench using the engine mount bolts on the firewall . With the fuselage positioned vertically I then put the rear half on it. I then tacked it together with cyano and then epoxy. I used fibreglass cloth and epoxy to reinforce where necessary. I think weight added will be minimal. I re skinned the sides with balsa from the inside and filled holes with slatted balsa, which was later sanded and clearcoted. I recovered with black solar film and re painted by hand with spare paint I had . I’m afraid the paint doesn’t quite match but I didn’t want to go out buying more. It looks fine to me but obviously is “very stand-off scale “. The radiator underneath was crushed flat but I just pushed it out stuck it with s bit of cyano then internally glassed and epoxied it . The outside saw a bit of body filler too. That was quite a fun repair 😉. The most important mod ‘( I think !) was swapping the tail wheel and replacing the over long solid billet aluminium tail wheel rod with a hollow alloy tube. That saved 30g on the tail !

Edited By Tim Flyer on 24/06/2019 20:41:11

Edited By Tim Flyer on 24/06/2019 20:42:08

[ASH.]

Thanks for explaining Tim.

I'm always amazed at what modellers can achieve with will and determination. I would have found that kind of repair quite daunting. Tacking with cyno is the first step and working in sections helps. I repaired my PC-9 a few times and she flew better than ever, but a broken fuse esp in that area is not for the fainthearted...

Out of interest, did you use finishing epoxy with the fibreglass or regular 30 min?

Edited By ASH. on 24/06/2019 21:07:20

[Piers Bowlan]

Very nice repair Tim, it looks great.

I expect you had, although you didn't mention it earlier but did you have some differential aileron dialed in with your set up? You mentioned that you were using quite a bit of rudder to help the turn as you said 'the right aileron seemed ineffective'. This might suggest there was some adverse yaw from the ailerons. Just a thought?

[Jon H]

When i flew it i found the ailerons behaved as i would expect for an early WWII fighter. I dont know how it was set up, but it was fine however it was!

The repair does look great, all we need now is a weekend we can get together with Chris and get them in the air!

[Tim Flyer]

Cheers chaps. Regarding ailerons they were set as normal(no diff) but I found afterwards that I must have accidentally altered aileron rate when adjusting settings after the maiden flight. I think I had left aileron at 80% rate but right at 60 % which was very strange..,

 

I’m having more repair practice now gluing back the tail on my P47 after a “non flying crash” . A freak wind blew the whole plane of our club table last Friday, and it hit the ground on its back breaking off the tail and damaging the rudder! It was very strange . We had total calm for quite a while...but then suddenly what seemed like a “twister” moved along the row of pits tables taking planes with it! I had only put the plane on the table temporarily so we could cut the grass!!😳

Edited By Tim Flyer on 25/06/2019 09:12:43

[Chris Walby]

Maiden time!

Jon, myself and the Hurricane met up yesterday late afternoon and after a spot of TX setting adjustments we were ready. No mixes on control surfaces at this point, but three rates on separate switches.

The 180 sprung into life if minimum effort and I wheeled it to the end of the runway.

Roll out looked good with minimum swing and gentle climb out. Needed aileron elevator trim and she settled in to circuit. Jon performed the usual maiden tests and noted the pitch down effects of the gear and flaps. Landing approach looked uneventful until close to the ground where it ran out of elevator travel. Jon add some throttle but the hurricane was having none of it. Bounce and nose over with minor bend in an oleo pin.

Mixes were added to gear/elevator and flap/elevator, the tank topped up and off we went again.

Again the roll out and climb out look good, gear up causes it balloon up momentarily (no issue) and the gear down full flap stall test occurs after a lot of elevator mushing. Final stall phase results in typical abrupt roll/dive towards the ground.

Then on one of the turns Jon lost TX control (signified by the engine revs dropping to idle (I think it was luck the engine didn't stop as the plane was in a low level dive). With control regained Jon brought her around for an immediate landing (more pressure!).

Jon brought her in and she really slowed up (really surprised me), became very mushy on the elevator and landed (with minor nose over).

Summary, Sounds great, looks good and major flying improvements with Jon's trimming and setting changes. Just needs a few more tweaks on the mixes and perhaps less flap and the RX issue resolved.

Thanks to Jon...another Hurricane survived its maiden

[Tim Flyer]

Well done I’m pleased it was successful. 😊 . You definitely don’t want to run out of elevator as I discovered in my crash . The fact that even an accomplished pilot like Jon still has nose overs etc with the very mushy low speed handling shows this Warbird certainly is no easy plane to set up and land. We went through 3wooden props and the canopy with my Hurricane. The set up seems critical. I flew my Seagull P47 yesterday with its Laser 100. That is a very friendly Warbird in complete contrast to the Hurricane. Still the challenge of taming the Hurricane is exciting and I’m sure It will be all sorted soon.

[Martin Harris - Moderator]

Posted by Chris Walby on 06/07/2019 07:45:39:

Then on one of the turns Jon lost TX control (signified by the engine revs dropping to idle (I think it was luck the engine didn't stop as the plane was in a low level dive). With control regained Jon brought her around for an immediate landing (more pressure!).

Summary, Sounds great, looks good and major flying improvements with Jon's trimming and setting changes. Just needs a few more tweaks on the mixes and perhaps less flap and the RX issue resolved.

Good news Chris but a bit worrying - your description sounds like failsafe initiating? What has pointed you to the receiver as the cause?

[Jon H]

Just to add my 2 cents to this i am still convinced that this model is a good one but my goodness does it make you work for it.

From the experience i had with Tim's Hurricane i was cautious on the first takeoff and as the model became 'light' much earlier than i wanted i spent the first 10 seconds of the flight just holding it down. I used 3/4 of the available down elevator trim and about half of the right aileron trim available.

Once there with the gear up and trimmed for a 45-50% throttle cruise i did a few rolls, which look stunning with this model, i did a loop and generally flew about the place on the lowest elevator rate available. Chris's example does not change trim as much as Tim's when airspeed changes, perhaps minor c/g differences are the reason? That said it does make a difference to the point that to do a wing over requires a shade of down elevator as you run in, power up to full, let elevator off to 0 to initiate a climb, add a little elevator once the speed starts to come off and the pitching slows, roll the wings over, feed in elevator slowly, more more more until its back at the stops over the apex of the wing over. into the dive and slowly bleed off the elevator, roll out and recover with down elevator applied on the run out to stop it climbing. I am used to this with my small Hurricane and my P39, but its not something most sport pilots moving to warbirds will expect. I wonder if we could set up a pair of cameras. One watching the model and one watching the sticks..hmmm

After enjoying the Hurricane for about 5 minutes it was time to come down. Gear and flaps down and i had a problem as i was unable to maintain altitude even with the elevator hard back against the stop at a speed was too high to land. High rates helped but i was unable to flare nicely and bounced. I decided to go around and began to add power but this just pulled the nose down faster so all i could do was chop the throttle and pull as hard as possible.

With the bent leg repaired and a mix set on flaps and u/c we went again. Takeoff was lovely with i think +25% elevator mix with the gear down. Flicking gear up kills the mix immediately even though the gear are in transit so there is a bit of lurching around during this phase. IF any dx8 experts know how to program the mix to wind off slowly as the gear come up that would be great.

Flew around, tested the reduced aileron rate. All was well.

Gear and flap down to prepare for a stall test and as i came into wind i lost the radio. I identified something was wrong before the sound of the engine going to idle reached us, the fact that it went to idle told me it was the radio. Boy was i glad when it came back but that was a long 3 seconds waiting!

With this concern i elected to land sooner rather than later but the flap elevator mix was all wrong and i needed almost full down elevator to make headway. Once low to the ground i was in a phase where it was almost like there was a 2 second time delay between moving the elevator stick and the model reacting. I suspect it was just out of the envelope and the resulting arrival was a little ungainly. If it wasnt for the radio concern i would have gone round and landed with either half flap or no flap, but i was sort of committed to the job at that point.

In the following discussion Chris and i think that the flap angle he has on the model is too great and the model is sitting on a beach ball of lift which is why its all wobbly and unstable. Next time out this is going to be the first thing to check out.

Tim is yours ready to go again? if so we should try and get all 3 of us together and hammer this out. If we can refine a baseline set of specs by averaging out the two models we can try to publicise them as i doubt many SG Hurricanes are surviving their maiden flights if their owners are following the instructions. If it comes down to it we can even inform perkins as they are the importer and can put revisions into the instructions.

[Martin Harris - Moderator]

Do you think the flaps may be disturbing the airflow over the tailplane? It might explain the reduction in elevator effectiveness. Maybe consider a higher elevator rate with flap as the master if the transmitter can support this functionality?

I'd still be very concerned at the loss of radio though and get Chris to address this as a priority.  Were you flying at your field or at Chris's?

Edited By Martin Harris on 06/07/2019 11:22:23

[Jon H]

i dont think it was tail blanking as the split flaps are under the wings and the tail sits quite high. I suspect the loss of response came down to the extremely low speed i was at at the time, and something about the wing where changes in angle of attack become exponential. I had this issue with my P39 which has a similar wing section.

The model is also relatively light for the lifting capability of the wing and i think the very high flap angle just put so much lift under the centre section the tips more or less werent doing anything. I forgot to mention that at this slow speed the ailerons really were useless.

Given its 'light' takeoff performance its possible the model is best landed with little or no flap. Unusual for a big warbird, but if it works, it works.

[Tim Flyer]

Mine is almost ready to go , but just needs a bit of foam padding under the wings as the fit is slightly uneven but that’s a 5 minute job at the field, I’m away next week so can’t do immediately.

[Jon H]

no rush, we can sort it as and when

[Chris Walby]

I have a couple of U/C pins to make (nice to have a few spares!) and change the RX out for the one from the Mossie (known good RX) and I am ready to go.

No major commitments for the next 2 to 3 weeks so just need the right weather conditions and Jon's availability.

Just need a time and place

Edited By Chris Walby on 07/07/2019 07:18:46

[Jon H]

Quite a sight at Old Warden yesterday afternoon. Something for us to work on!

[Martin Harris - Moderator]

Aaaargh - to think I was less than 10 miles away as the Hurricane flies entertaining family and peeling spuds!

[Cuban8]

Yes, was a memorable day - should have been eight Hurricanes but the missing one was apparently U/S with a tailwheel problem at its home base. I though one of the Hurricanes that arrived early in the day cut it a bit fine on landing. Slightly downwind towards the road not a lot of room left at the end of his run. Good show, even got some of the Edwardians up at the end.

Not so sure about the model exhibition - was it BMFA or LMA? No info on the models, no literature that I could see. Flight sim trailer tucked away in the corner and not particularly obvious as to what it was. I looked over the models for ten minutes and nobody engaged me to ask if I might me interested in models or flying.

Go near the traction engine or other vintage vehicles and you're given an impromptu tour and info almost immediately .

[Chris Walby]

New U/C pins made and fitted + additional RX remote in air scoop/repositioned others so she is ready to go!

Jon, Tim,

Weather is looking ropy (S/E) at the moment, but do either of you have a preference as to flying field and time/day?

[Jon H]

if the weather man is right next sunday is looking good for the aylesbury strip and would be ok for Tim's field at north london too

[Tim Flyer]

Hi Chaps. I’m afraid I’m up in Scotland from 19th to 27th July so I’m afraid I won’t be able to join then .

Hopefully we can get a day next month at short notice . I can also do a day in the week if that suits . I’m very happy for you guys to come to my patch then . Here is our website for info **LINK**

Our very long main runway runs East /West and we do have a cross runway running NE/SW, but for Warbirds the main runway is way better

[Jon H]

Well. Today was an interesting and somewhat head scratching day.

Long story short, with the rx tweaked Chris again let me loose with his hurricane to see if we could sort it out. As before, takeoff and normal flying about were no problem and the model looks and feels lovely in the air. I made a small tweak to the aileron rates but nothing major.

So..landing.

Well i must have done somewhere around 30 approaches with the bloomin thing with different settings on things but do you think i could get it down softly? It would always end up in this slow porpoise and bounce off the runway. Combined with the tendency to pitch down when power was applied a few of my aborted attempts were quite interesting!

The root cause of all this was that same slow/damped elevator response i talked about before. It meant that i was unable to just catch the flare and touch down softly enough not to bounce. I was able to replicate it at high altitude and after some fiddling with the rates i found that a higher elevator rate with half flap gave the model a much better feel on the approach.

This proved successful and after plenty of practice two good landings were performed. The somewhat gusty wind did not help us at all, but i think we now have settings on the model that will work well on a day that isnt so blustery.

As a side note, the high rate i am using is still only about half of the seagull recommended low rate. While much improved the model will not just land itself, you have to fly it right down to the ground so anyone thinking of buying one best be prepared for that.

[Tim Flyer]

Great to hear you sorted it out, well done! Certainly doesn’t seem to be a “ lazy day flier” .