Seagull radial rocket

[Tom Ling]

Hi guys I'm looking at a seagull radial rocket for a 90 2 stroke should fit in nicely and it looks a nice plane but has anyone got any reviews of it on here? Thanks tom.

[Former Member]

[This posting has been removed]

[Tom Ling]

Ahh thanks il try and find the review, yer it does look a little bit on the week side but they all have the bad points, as long as it's not actually a bad design hopefully it will stand up.

[Pete B]

Sept 2015 edition...

Pete

[Tom Ling]

Thanks guys I must of missed that one, have read it and it does look smart, just need to open up the cowl and be gentle on landings!!

[Ron Gray]

My wife bought one for me for my birthday a week ago, am planning on fitting a Laser 100. Is there any interest in a build blog of it bearing in mind it's another ARTF rather than a plan or kit build?

[Ron Gray]

I decided to put together a few shots of the assembly (well its hardly a build!) of the Seagull Radial Rocket, but more importantly my modification to the U/C!

General construction is first class, unlike the Seagull P40 I had!

Plenty of glue appears to have been used and good strengthening to the bulkhead, which is good as I planned on using a Laser 100 to power it.

Control surfaces were hinged using the supplied furry mylar hinges and CA, I use Vaseline to protect the covering to prevent it 'milking' with CA fumes. I also make sure that there is only a very small gap between the surfaces.

Control horns were an issue, whilst fine for the rudder they are much too big for the wings and needed to be cut down.

They also needed the glued portion to be shortened otherwise they pushed against the film covering.

Servo trays appeared to have plenty of glue and good strengthening

Next I needed to source the servos from my servo drawer

With servos fitted it was obvious that the output arm slots needed to be reformed as the arms fouled the pre cut ones

Out with the Dremel

[Tim A]

Keep the info coming Ron I am watching with interest. One thing I have noticed from the manual (won't get the plane til January) is that the servo mounts appear to be sized for Futaba standard servos, I use Hitec ones which are fractionally smaller so some mods may be required.

[Ron Gray]

Next to check was the elevator joining wire, I've very rarely come across one that has been formed correctly, not sure if you can see the unequal bends in this photo.

Back to the servos, extension leads fitted, I remove the outer casings and use heat shrink

And SBUS used to reduce the number of connections necessary to the Rx (FrSky X4)

Turning attention to the engine, the Laser 100, whilst a large(ish) engine fits quite nicely in that big cowl and I decided to fit it 'sidewinder' with no silencer, just flexi exhaust. This has now been changed and there is a remote silencer in there now!

The cowl needed baffles to aid engine cooling, mine is made out of balsa

And a print of a radial engine stuck to the front and then the whole lot fuel proofed.

Cylinder head cut out isn't too obvious. well not from a distance it isn't!

And the finished 'plane waiting for its maiden flight

[Ron Gray]

Now the maiden flight was excellent, a bit too much throw on the elevator but all other controls fine and very little trimming required apart from a bit of ballooning when flaps were deployed (now sorted with down elevator mix).

BUT the landings............or more to the point the U/C. What a poor design they are. The first landing was fine but the second landing saw one leg pull its mounting block out of the wing, no major damage and the block was duly stuck back in with a healthy amount of epoxy. The following week I took it out again and on its third landing I decided to use the grass strip next to our tarmac (it looks nice on grass was my reasoning). Big mistake, out popped the U/C mounting block which put paid to the flying for that day.

The problem with the U/C is that there is no give whatsoever in it, you can see what I mean from this photo

And this is mounted to a block which is stuck into the wing

And that's the bit that pulls out causing this damage

Next instalment is how I have modified the U/C

[Ron Gray]

OK so having had a couple of flights where the U/C pulled out from the wing I decided that a better form of U/C was necessary and to this end decided on a torsion bar type fitting. This involved removing the parts of the U/C that plugged into the wing and fixing two extensions to the legs at 90 degrees with end bent down to plug into a new hardwood support mounted to the wing.

Hardwood support with groove for torsion bar part of U/C (holes at end of bearer were too near the end).

Recovered front wing section with sheet balsa

Then recovered wing section

U/C fitted and clamped in position

Finished job

Actually that wasn't the finished job! I took it out again but it had a nasty tendency to nose over both on take off and landing so I bent the legs forward by about 5 degrees, now it is absolutely steady. I also changed the wheels for slightly larger, low bounce ones and this has now transformed the Rocket.

In terms of flying, all I can say is that with the Laser 100 up front its certainly lives up to its name and flying it Reno racer style (which is what this model is based on) is great fun, pylon turns at full throttle are great fun. I have also found that the flaps are a must if there is little wind blowing to slow it down.

In conclusion, having made the U/C mods I now have a 'plane that is a joy to fly and a great adrenaline rush!

[Graeme Poke]

Hi Ron,

I am interested in buying a Radial Rocket. I have a Saito 80 and was wondering if it would have sufficient power to do justice to scale flying given that it is a Reno racer. And any comments you may have on the model. Are you happy with it? Any thoughts please? Cheers Graeme

[Ron Gray]

Hi Graeme

i would think that the Saito will be fine, I purposely overpowered mine with the Laser 100, it would be happy with the 80, because I wanted a ‘speed machine’! It’s good fun flying it and steeply banked high speed turns are a joy. The big problem is the u/c, the design of the gear is very poor and is prone to pulling out as you can see from my earlier photos. The torsion bar mod that I made improved it no end but I also raked the legs forward a bit more to help prevent nose overs. Also watch that the spats don’t catch on the wheels, mine did and caused a nose over which damaged the cowl!

[Graeme Poke]

Thanks Ron, I'll give it a bit more thought before committing. In other words, talk myself out of it.

I am due for a tax return so I'll see how that goes. All the best Graeme

[Bob Cotsford]

As this threads has been Lazarused, I'll add a question for Ron. How have you engineered the leg covers to cope with the radial movement? There doesn't appear to be much clearance between the tops and the wing underside. I have a Blackhorse Provost which I've done a similar torque rod mod on but so far I've not tried to refit the leg fairings due to the need to think out a mounting system for attaching them to the oleo and wing.

[Ron Gray]

Well spotted Bob! I cut the top of the leg covers back at a slight angle (not shown in the photos above) then stuck on some white Solartrim to cover the gap. Being flexible the Solartrim deforms / reforms as necessary. By the way, the fairings are attached to the legs by means of a hardwood block which has a groove in it and is fixed to the legs with saddle clamps, the fairings are then mounted to the blocks with 2 small screws.

[Bob Cotsford]

Cheers Ron. If I can find the Provost's 'trousers' I'll see about fitting them again.

[Lubomir Bakalov]

Subscribed!
I've got one.
Guys
Can you share, please, the used servos, thank and AUW.
Where is your CG and how it is going with?
What engine will confirm the name?

I have SC FS61AR, OS FX61, SK110, SC FS120AR, RCGF20,
but suppose the engine weight of around 1kg will be not good idea for balance.

Thank you in advance!

[Tim A]

Ron, finally got mine to the almost ready to fly stage (had a lot of interruptions over winter, not much building or flying done!). I also encountered the same problems in the build/assembly? as you did.

Would be interested to know where your CG ended up? Mine is 15mm forward of the 88mm mark as per MFS. To move it back I will have to cut the servo platform in order to move the 5S battery back any further. Don't wish to add any further weight if it can be helped as it weighs 7lbs 7oz at the moment. Although it has plenty of power at approx 140 watts per lb.

Thanks the CG the last thing to sort before I go and rip the undercarriage legs out.

 

Edited By Tim A on 28/10/2019 01:26:02

[Ron Gray]

I’ll check it out later on today. The u/c is still a PITA, I’ve ended up raking mine forward to prevent nose overs.

[Graeme Poke]

Hi All, After Ron gave me some advice, see further up the thread, I bought one of these. Since I'm spending more time in the workshop (you know why) I decided to put it together.

I started with the engine, Saito 80, and ran straight into trouble. The instructions state that the distance from the firewall to the thrust driver is 113mm. However, if I do this (with some difficulty pushing the cowl on) the lines/paint work on the cowl do not line up with the fuse. But if I take the distance out to 133mm it's spot on. Is it a mistake in the manual or am I missing something?

Has anyone else had this problem please? Happy building, Graeme

[cymaz]

Graeme

if you look HERE..page 11 the manual gives another measurement. Try emailing Seagull, they’re should get back to you 

Edited By cymaz on 29/03/2020 06:05:02

[Graeme Poke]

Thanks cymaz, more confusion.

That manual is similar but there are some differences. On page 17 of the manual you linked to, the electric set up states 145mm. In my manual it's 113, same as IC. Doesn't make sense. Why would it be 125mm for IC, 145mm for electric in your link?

I'll do as you suggest and email them. Cheers Graeme

[Ron Gray]

Graeme, I will go and measure mine to see what I have.

[Ron Gray]

Mine measures 138mm from back of spinner backplate to firewall.