Seagull Boomerang Trainer Experiences.

[David Davis]

Just a few notes on my experience with the Seagull Boomerang trainer. 

 

This is my favourite ARTF trainer.It's the model on the right in the picture below. Note I said "ARTF trainer," my all time favourite trainer id the Telemaster 40.

 

I like the Boomerang because its semi symmetrical wing section allows it to fly in a breeze without it being tossed about too much as a trainer with a Clark Y or similar wing section would. However, it is a fairly heavy model, waighing in at nearly 6lbs or 2.8kgs. It has a fully sheeted wing and it flies fairly quickly so I tend to start retired trainee pilots on a slow-flying vintage model before moving them on to the Boomerang.

 

My current Boomerang is my second. The first spread itself deep and crisp and even all over the ground when I gave my trainee too much time to correct his errors! My fault of course. I had inititially fitted an Enya 50. This engine has six bolts holding down the cylinder head but I discovered that one of the threads in a bolt hole had stripped and though the engine ran very well, there was a slight oil leak at the position of the stripped thread which suggested a blow between cylinder and the cylinder head. Trying to bodge the job with PTFE tape didn't work!

 

So I replaced the Enya with a Super Tigre 40. The Super Tigre runs very well and flies it alright but it requires almost the full length of our tarmac runway plus a dab of up elevator to get it to unstick. A beginner would have problems taking off with it so I'm going to replace it with something more powerful.

 

I suppose that I could fit the Enya back in place but fear damaging the engine if I continued to run it. I'll have to see whether Steve Webb has a crankcase for it. Other runners and riders include an Irvine 46 and an OS 61SF, then I've got a couple of OS52 Surpasses doing nothing. I also have an old Enya 45 but I don't think it's much more powerful than the Super Tigre. Decisions, decisions. 

 

Which engine from those listed above do you think that I should use?

 

The point of all of this is that in my experience with the Boomerang, if you're a beginner, and if you are going to buy a Boomerang, you will need a bigger motor than a 40 for it. A good 46 would be about right.

 

As always, I appreciate the views of others.

 

 

[Jonathan M]

My ARTF Boomerang has an OS46FX in it, which seems just right (neither over- nor under-powered) for the job, so I'd say pop your Irvine 46 into it and give it a whirl.

 

I increased the fin area by 25%, making it slightly more useful as a general sports/aero flyer for myself.

 

Re older trainees, the majority that start on lightweight foam things often - in my experience - become frightened of proper heavy models and simply can't make the transition.  They continue to turn up with their 'safe' little piece of foam, struggle to fly it in any sort of breeze, then go home for a few weeks.

 

 

Edited March 29, 2021 by Jonathan M

[Brian Dorricott 1]

If the Boomerang won't get off on a runway like that it must be underpowered !  SC 46 powered my first one like a dream just right , 2nd one has a Saito 62b bags of power and nicer noise .

[Graeme White]

Mine has an irvine 40 which is marginal in getting off the ground in time but once up its fine and seems fairly reliable. Got me through me A end of last year ?

[David Davis]

3 hours ago, Brian Dorricott 1 said:

If the Boomerang won't get off on a runway like that it must be underpowered !  SC 46 powered my first one like a dream just right , 2nd one has a Saito 62b bags of power and nicer noise .

It will take off Brian but it requires virtually the full length of the runway and a nudge of up elevator to do so. This would be difficult for a beginner to achieve so I'm fitting my Irvine 46 to it and have ordered a new crankcase for the Enys 50 from Steve Webb Models.

[aidan mcatamney]

My new Boomerang arrives this afternoon.   I'm keeping it tryicle undercarriage,  but intend to put slightly larger rubber wheels on the model to give it better handling over grass.  Did anyone upgrade their wheels on the Boomerang and did the extra weight affect it much?  

[Denis Watkins]

Added double wired triangulated undercarriage, and 3 heavy Dubro Low Bounce air wheels

With big improvement on ground handling and landing without bending the old single wire mains, and no difference in flight.

this model can carry weight and just improved wind handling

Edited December 7, 2021 by Denis Watkins

[aidan mcatamney]

20 minutes ago, Denis Watkins said:

Added double wired triangulated undercarriage, and 3 heavy Dubro Low Bounce air wheels

With big improvement on ground handling and landing without bending the old single wire mains, and no difference in flight.

this model can carry weight and just improved wind handling

Thanks Dennis.   Did you keep all 3 wheels the same size?.  I always do,  but I know that some people prefer the nose wheel slightly smaller to the mains?

[Denis Watkins]

I put the original foam wheels in stock, as I find them just too hard, and fitted three 2.75" Dubro.

[John Muir]

I had a Boomerang to get me back into the hobby after a break. I replaced the wheels with rubber ones because mice ate the foam ones. Didn't make any difference to the plane at all. All the same size as the originals. Mine flew on an ancient ASP 40, which flew it fine but was terribly unreliable and gave me loads of deadstick practice, then a Super Tigre G49, then a J'En 37, which broke, and finally an SC 36, which flew it quite nicely until the covering gave up the ghost and I retired it. Still have the wing though.

Edited December 7, 2021 by John Muir
spelling

[aidan mcatamney]

7 minutes ago, Denis Watkins said:

I put the original foam wheels in stock, as I find them just too hard, and fitted three 2.75" Dubro.

Thanks Denis.  Did you go for the smooth or treaded Dubro low bounce wheels?  

[aidan mcatamney]

6 minutes ago, John Muir said:

I had a Boomerang to get me back into the hobby after a break. I replaced the wheels with rubber ones because mice ate the foam ones. Didn't make any difference to the plane at all. All the same size as the originals. Mine flew on an ancient ASP 40, which flew it fine but was terribly unreliable and gave me loads of deadstick practice, then a Super Tigre G49, then a J'En 37, which broke, and finally an SC 36, which flew it quite nicely until the covering gave up the ghost and I retired it. Still have the wing though.

Thanks John.  I have 4 spare engines here that I could use on the Boomerang.  Fourstrokes have always been my favourite,  simply because I love the sound and I run them slightly rich to give a trail of smoke.  A Saito 62, an OS 53 Surpass, an OS 46fx two stroke and an OS 46ax which is almost brand new.  My heart is lying towards the 52 fs simply because its been in its box for over 3 years and I'd like to make use of it.  Though the Saito would give me much more power?  

[John Muir]

If you are actually going to fly it as a trainer rather than a sport aerobatic model, then the 52 will be fine, I'd have thought. The other engines will give a sprightly performance if that's what you're after. One of my trainees had a Boomerang with a 46 in it and I always felt it was more than he needed. It spent a lot of time at low throttle which these ABC 2-strokes don't like much because they cool down so we'd sometimes get a big puff of smoke and some hesitation when we opened up for a go-around. I used to like chucking my Boomerang around even with the 36 on it. With a little bit of energy management you could string together a series of loops, rolls and stall turns if you wanted. Nice aeroplane.

[aidan mcatamney]

20 minutes ago, John Muir said:

If you are actually going to fly it as a trainer rather than a sport aerobatic model, then the 52 will be fine, I'd have thought. The other engines will give a sprightly performance if that's what you're after. One of my trainees had a Boomerang with a 46 in it and I always felt it was more than he needed. It spent a lot of time at low throttle which these ABC 2-strokes don't like much because they cool down so we'd sometimes get a big puff of smoke and some hesitation when we opened up for a go-around. I used to like chucking my Boomerang around even with the 36 on it. With a little bit of energy management you could string together a series of loops, rolls and stall turns if you wanted. Nice aeroplane.

Thanks John.   I was only intending to fly it as a trainer, nice and sedately.   But if I go ahead with the OS 52 surpass and I feel I'm not happy with it as far as being underpowered goes,  then I can just swap it out for some of the other engines mentioned.  I'm just dead curious about the 52 surpass on how it would perform on this plane.   Yes looking forward to putting the plane together John.  

[Zflyer]

Probably no help at all but converted mine to electric. 4 Max PO 5055 595 on a 4s. Ruddy marvellous

[aidan mcatamney]

46 minutes ago, Zflyer said:

Probably no help at all but converted mine to electric. 4 Max PO 5055 595 on a 4s. Ruddy marvellous

Many thanks. 

[Jonathan M]

I fitted 2.75" Dubro low-bounce as our patch can sometimes be a bit bumpy.

 

Denis' U/C improvement sounds very worthwhile - I'm frequently have to bend the wires back into correct position!

 

As to engine choice (as I said before) a 46 would be perfect, but if you want to see what the 52 FS is like then fit that.  But, if you're not altogether happy with it flying, then it'll be pretty easy to retrofit the two stroke.

[aidan mcatamney]

2 hours ago, Jonathan M said:

I fitted 2.75" Dubro low-bounce as our patch can sometimes be a bit bumpy.

 

Denis' U/C improvement sounds very worthwhile - I'm frequently have to bend the wires back into correct position!

 

As to engine choice (as I said before) a 46 would be perfect, but if you want to see what the 52 FS is like then fit that.  But, if you're not altogether happy with it flying, then it'll be pretty easy to retrofit the two stroke.

Thanks Jonathan,  the Boomerang arrived today and I checked it all over for damage and thankfully its OK.   Its a nice looking model with its bright colours, so tomorrow I will get a coat of polyurethane varnish on the tank bay and firewall.  Will also check for any loose wood joints and add epoxy where it is needed.  I've  already got the servos,   I use Hitec 422 in all my planes.  Will order three 2.75 Dubro low bounce wheels and a Dubro nose wire gear as its strong and I have one one on my Hangar 9 Meridian and it never gives any trouble.  

[aidan mcatamney]

On 29/03/2021 at 12:37, Jonathan M said:

My ARTF Boomerang has an OS46FX in it, which seems just right (neither over- nor under-powered) for the job, so I'd say pop your Irvine 46 into it and give it a whirl.

 

I increased the fin area by 25%, making it slightly more useful as a general sports/aero flyer for myself.

 

Re older trainees, the majority that start on lightweight foam things often - in my experience - become frightened of proper heavy models and simply can't make the transition.  They continue to turn up with their 'safe' little piece of foam, struggle to fly it in any sort of breeze, then go home for a few weeks.

 

 

Jonathan, when marking the drill holes for mounting the engine.  What measurements did you use for positioning the engine?  The manual says 110mm, but to me this looks too short?  

[Jonathan M]

I'm at 100mm to the rear of the prop.  No point in going any further forward as it'll just mean more horrid tail weight!

 

[aidan mcatamney]

35 minutes ago, Jonathan M said:

I'm at 100mm to the rear of the prop.  No point in going any further forward as it'll just mean more horrid tail weight!

 

Thanks Jonathan.

[Paul De Tourtoulon]

Can't you move the radio battery back ?.

[Jonathan M]

My own battery is already bang under the TE... yet still needed some tail-weight (for me, not for learners).

 

Good job Aidan didn't go with the four-stroke!

[aidan mcatamney]

1 hour ago, Jonathan M said:

My own battery is already bang under the TE... yet still needed some tail-weight (for me, not for learners).

 

Good job Aidan didn't go with the four-stroke!

No, decided to keep the fourstroke for something else and use the 46fx on the Boomerang with an 11x6 apc prop.  So otherwise Jonathan, I need to bolt the engine in as far back as possible?

[aidan mcatamney]

1 hour ago, Paul De Tourtoulon said:

Can't you move the radio battery back ?.

Yes Paul, I will move the battery back as far as it takes to get the the balance right.  Thanks.