NJR Mirus 40 (Ken Stokes design)

[Tim Donald]

I'm building a Mirus 40 that Nick Reeves is now producing.  I used to have an original back in the day.  Just wondering what is the biggest size IC engine anybody has tried in one of these?  Since .40 size is not really a thing anymore I was thinking about putting a .46 in but the OS Max .55AX is only slightly heavier.  Has anybody tried that?  Wondering if it will balance ok and if there is any performance gain?        

[SIMON CRAGG]

I had one of the original Ken Stokes versions.

 

Went like stink on an Irvine .46 and Weston Power Pipe!

 

Sold it on, as way to fast for me at the time.

[Peter Miller]

I had both sizes.

The .25 size version was in a vertical dive and refused to pull out.  We worked out that the elevator pushrod wire was too thin and there was no support to stop it bowing  so the elevator didn't move!

The model went straight through a very large, tall tree....VERTICALLY.

The ST25 was a write off, never mind the shredded balsa!!

[Tim Donald]

I had an original back in the day (40 size).  I was fairly new to flying power at the time and flew in front of the sun.  Ended up going in vertically at full speed and that was that for the plane and the engine 😂.  I'm hoping this one lasts a bit longer !  

[Edubarca]

Hello greetings from Colombia. I would like to build the MIRUS  model. I don't buy a kit because transportation to my country is extremely expensive and I like to build from plans, Can you tell me where can I purchase plans for this model? 

Thanks

[Martin Harris - Moderator]

Have you tried contacting NJR?   They might be sympathetic to your situation and be willing to sell you a plan. 
 

https://www.njrmodelling.co.uk/contact-us/

[Alan Gorham_]

It doesn't come with a plan!

[Gee Bee]

Ken Stokes did occasionally offer plans for the Mirus on E-bay, so it would be worth watching what is being listed - though it may take some time to catch the listing. 

 

I did manage to get a copy of an original Mirus Kit plan (I think it was the .25cu in version) from a private seller on the bay a few years ago. But that was a matter of luck, and is not a reliable source.

 

I also found a picture of the original Mirus kit box label in my records.

 

[Gee Bee]

Just to confirm, the plan I've got is an original KDS models kit plan for the .29-.40 engine range. The kits had vennered foam wings, but could possibly be substituted with solid sheet wings (Like, or similar to, the RCM&E 'Gulp' flying wing design from the '90's).

The rest of the structure is simple balsa & ply.

 

The Mirus was a simple to build, but fast sport model that was popular from its introduction (mid 90's ?), but I do recall some were quite short lived models as the small size & speed could easily lead to disorientation issues with the inevitable conclusion. 

[RottenRow]

9 hours ago, Gee Bee said:

its introduction (mid 90's ?)

Mid ‘80s I’d say. I remember watching them at the excellent Cranfield Expos, and Dave Bishop commentating on them from the top of his van.

 

Brian.

[Gee Bee]

Hi Brian,

 

I remember the Ripmax team using what I think was the smaller version of the Mirus but fitted with the MDS 15 'Speed' engine with rear exhaust port & cast tuned pipe (A control-line speed type motor with no throttle control).

 

Those would most likely have been from the mid-90's. They always put on a convincing display, which led to the sale of several Mirus kits at that event ...... & the couple of Mirus models that came to one of our local clubs back then were also impressive - but had short service lives ..... especially the one that had the same MDS 15 Speed engine as per the Ripmax models.  

 

A good reminder of the old saying/proverb that 'Power comes with responsibilities'. 

 

Living in the North West, I do remember seeing them at the Woodvale shows near Southport, Lancashire (Which ran annually on the first weekend in August - but I think they stopped running that event). I also remember Dave Bishop doing the commentaries at those events.   Happy Daze !

 

Cheers & safe landings   - GB