No 60 size

[paul f]

Being ex old school (vario 60,concept and shuttle 30)

How is it that most new models are either 50 or 90?? and not many 60 size??

Paul

[Andy from Sandy]

The 50s are yesterdays 30s and 90s are yesterdays 60s. You can put a 60 or 70 in a T-Rex 700 and it performs quite well.

[Steve]

You should also remember the Freya - it's still available as both a 60/70 version and a 90 version. It's exactly the same heli apart from the main gear and main shaft. Same size etc.

[Heliheaven]

In the words of Jethro,

'What happened was!'

The OS 61 SXH-WC was the power house of the day and to get the most power from it 30% nitro was best. Originally some flyers started trying the new generation of 91 sized engines and they where able to obtain the same power from a 91 on 10% nitro fuel on a muffler as they could from a 61 on 30% and a full tuned pipe.

Once the 90 engines became established model designers realised that there was more available from a 90 and so the latest generation of helis will happily swing 710mm blades up to around 2000 rpm at +/- 15 degrees!

The overall size of the models has changed very little and of course, now people are running their 90's on 30% nitro fuel and still looking for a little more power!

[Steve]

And the same kinda thing happened with the metamorphosis of 30s into 50s.

And now our 50s are becoming 53s,55s, 56s and even 57s, so we've now just about got a 60 size heli in a 30 size airframe.