Morley Prototypes

Morley Sea King (1979)

Development started in 1979 using a fuselage of the Sea King designed by Chris Garside and supplied through Preston Model Centre.  Incorporated a unique safety feature and instead of using one large engine it had two 40 size engines driving through individual clutches to a common gearbox; in this way if one engine failed there would be enough reserve power to at least make a controlled emergency landing and thus, hopefully save the model.  Full scale OD five blade main rotor head and four blade tail rotor was used along with gyro's for main rotor control.  Interestingly when this assembly was tested on a development airframe the vibrations shook the model apart however, the layout had proved it could work and so development was continued in order to iron out the vibration issue.  By late 79 it had flown though vibration was still an issue but as Jim says:

 

The two 40s have a common exhaust outlet and the noise, with a slight throb to it, is beyond the imagination. The model is big too, and unusual so far in that to retract the undercarriage is quite a novelty. Unfortunately, the five blade head still has problems, vibration and variable phase lag to name but two, so the model is flying on the standard collective pitch head with longer blades.  The two engines each have a drive belt and clutch onto a separate pinion on the crownwheel.  Four gearbox casings were utilised in making this set up, the clutches are leading shoe so that on one engine failure the clutch will drop out of engagement easily. The tail rotor is taken from the rear pinion assembly.

With this arrangement you can start one engine, set it up properly even to the point of trying to lift off - it won't, it weighs 11lbs - stop that one, start the second engine, set up, restart the first and you're ready.  The power from the two 40's is phenomenal, the model lifts off at nearly full revs but only about half throttle.  Makes the up and down a bit sensitive on collective and no, I haven't had an engine flame out yet, or a deliberate one - don't want to push my luck too far.  I've already had one near disaster - but I have a feeling that collective should be on a different servo to the throttles  for this.  There seems no snag in having the throttles linked though I half expect there would be.  Incidentally, the model is legal, as the full size Sea King has two engines, the SMAE rules allow over 10cc in that case.

I originally intended pumping the fuel up from a low tank but scrapped the idea for quickness of building and have two tanks, one at the back of each engine. Not really very nice as one tank sits between the swashplate servo's. The T/R and retract servo's together with the Rx and Ni-Cads are down in the nose.  One snag with the model is vibration, a lot of it is not heavy, another snag is the layout and tension convinces me to try to start the second engine in reverse.  I'm getting used to it but I've felt very foolish a few times. 

Jim goes on to mention a near disaster when taking a picture on the water as a float filled up and rolled the model over; luckily it was 'caught' in time and didn't sink.

One aspect that immediately comes to mind regards the comment of two engines providing a measure of safety if one fails BUT all servo linkages fixed together.  With two engines at a setting for the hover, if one fails then the other would need to make up the power difference and this could only be achieved by advancing its throttle.  However, with a fixed linkage set-up, advancing the throttle also increases the pitch and thus stalls the engine and slows it down.  This was proved when Jim tried some experiments for engine failures and unfortunately, in the pre-computer radio age, to provide some sort of 'automatic' throttle increase function would have been extremely complicated and so this aspect was not pursued any further.

The helicopter was flown quite a few times and by a number of other pilots so it did prove successful but, way too complicated to even consider production given that Jim was still in the process of setting up for his first kit which was to be the 'simpler' Hughes 300.

Morley Bell 47G 'twin' 19 engines (1979)

1979 Twin engine version.

As well as fitting twin engines into the Sea King project, Jim also tried it out on his Bell 47G.  This model was fitted with two 19 size engines in a Vee formation driving through belts and a common clutch.  Unfortunately this meant that you had to start both engines together using a double glow lead and if one engine 'flamed' out, the drag was enough to stop the other engine.  In addition, to tune an engine required removing the others drive belt which was very inconvenient and made it quite a complicated affair to set up and tune.  Despite the inconvenience of this arrangement the model did fly well.  

Morley Chinook (1980)

Two Morley 2C chassis joined together and powered by a single OS60 with Jim provided the parts and Warren Bailey did the building and testing; described as not exactly vice free in flight - probably quite an understatement...!!!

Morley Bell 47G 'twin' 30 engines (1980)

Nov 80 Advert - 1/7th 47G now built with twin Irvine engines

Jim considered the original twin 19 arrangement to be a bit 'Heath Robinson' and decided to make his next twin Bell 47G using the larger 1/7th scale version and this time with two Irvine 30 motors and twin clutches as per the Sea King.

Morley Osprey

 

Morley Rotodyne

 

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