SC 120FS - will it pull the larger Black Horse Chipmunk

I have an SC120FS lyinh idle as a result of my incompetence! I fancy a Chipmunk but the smaller BH model would appear not to need such a large engine. The 45cc petrol version is only a few inches bigger than the RM276 plan version which seems to take a 90.

 

has anyone any suggestions, please?

It does seem a bit OTT - certainly if you're looking for reasonable scale performance. I wonder whether the tail has been built heavy to counteract the engine weight or if the battery is designed to go quite far back? If the latter is the case then I would imagine that with the 120 you should end up with a lighter overall package which probably is no bad thing.

 

My Airsail Chipmunk:

 

 

(quite a bit smaller at 1/6 scale - 69" span but not particularly light at 8 1/2 pounds with on-board glow etc.) is adequately powered by an OS 52 - although many people overpower these models with 70s and even 90s. I use not much more than 1/3 throttle for take-off to avoid it getting off in a couple of lengths, which looks most un-scale like. The designer told me that the prototype flew on a "well used OS40FS" and I can easily believe him.

I have a OS91FS in the smaller BH Chipmunk and although the extra power is fun, it is, in my opinion, overpowered. The full "scale-like" flight envelop can be done on 1/2 to 2/3 throttle.

 

In my view a 70FS would be fine in the smaller one. Given that, I can't see a 120 failing to deliver the goods for the larger Chippy - especially if you are a fan of scale-like flying performance.

 

BEB

I have a fairly small electric motor in my big Black Horse Chippy and its fine if you are happy with scale aeros. I have to enter a loop from a shallow dive, but to me that's fine.

Andy Glover has been campaigning one of these Chipmunks in flying only at scale comps all over the UK, with great success. The motor he uses.... an SC120

Mine weighs around 11lbs and is a great flyer. Ditch the pilots though they weigh nearly a pound.

Thanks, chaps, that was a swift response, I think i take that as a "go for it"

 

Happy landings

 

Pete!