24 Mar 01 - Magazine
flying shots added. 24 Mar 01 - Magazine
flying shots added.
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| No of launches / Time | 23 | 1 hours 13 mins | |
| Wingspan | 47.2 " | 1.2 m | |
| Wing Area | 390 in² | 25.2 dm² | |
| Flying Weight | 4 lb. 8½ oz | 2.05 kg | |
| Wing Loading | 26.8 oz/ft² | 81.5 g/dm² | |
| Wing Cube Loading | 16.3 - Racer (OK for fast jet) | ||
| Motor | Graupner Ultra 930-6 8v | ||
| Ducted Fan Unit | WeMoTec Eco Fan Pro | ||
| Batteries | 12 Sanyo RC-2000 cells | ||
| Speed Controller | Graupner Power MOS 48 | ||
| Receiver | Futaba FP-R105M - PPM - modified to 7 channel - 35 MHz | ||
| Servos | Elevator - Ripmax Diamond SD200 | ||
| Ailerons - 2 Hitec HS-101MG | |||
| Static motor parameters | Graupner Speed 600 Race 8.4v
- 32.5A at 8.7v, producing 18oz (5N) thrust after 30s. Graupner Ultra 930-6 8v - 38A at 13v and producing 30.5oz (8.5N) thrust after 30s. The fan turns 19500 rpm at full throttle and 13600 rpm at half throttle. |
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| Flight performance | Graupner Speed 600 Race
8.4v - Successfully flown but very underpowered, I am unable to fully test the model due
to the lack of power. Can't gain much height due to lack of power. Unable to complete a
loop even with a dive to gain speed. Graupner Ultra 930-6 8v - The flight envelope has really opened up. The model is very quick in the air and behaves just like a jet aircraft. Loops can easily be flown although I haven't tried without a slight dive first. Flight duration has increased and 4 minutes is normal on full power, with longer achievable using the throttle. |
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The fuselage construction is a liteply keel with a balsa (ladder type) structure built on both sides. The nose is built up from soft balsa. The duct is made from thin plywood with ABS mouldings outside for cosmetics. The wing is veneered foam with balsa end caps. I have finished the model in the colours of the French Armee de'l Air display team aircraft.
19 Sep 98 - Attempted the first test flight. After about 5 failed hand launches it tip stalled and cartwheeled into the ground. This damaged the forward fuselage, but won't take too long to repair. I'll have to bungee launch it next time to ensure it reaches flying speed & unloads the fan.
17 Oct 98 - I have now managed to fit in a few flights using a bungee launch, but the model is underpowered with the Graupner Speed 600 Race 8.4v. It can't increase the number of cells with this motor as it is already drawing 32.5A static which is really over the maximum for this motor.
17 Jun 99 - I have fitted a Graupner Ultra 930-6 8v motor and carried out a few changes to fit 12 RC-2000 cells. I am using my Graupner Power MOS 48 controller and have fitted a 270mAh NiCd pack to power the RX. I have also completed the fitting of the ducting and covering of the model.
10 Jul 99 - Experienced loss of radio signal during the start of the flight today. It actually caused very little damage despite the model cartwheeling extremely well. I think it was due to the RX aerial lying over the rear fuselage and being partly folded back on itself. I wanted to fit a smaller RX anyway, so this seemed like a good time. I am thinking of fitting the landing light into the nose as it is looking a bit scruffy.
6 Aug 99 - Last Sunday (1 Aug 99) the fuselage was extremely badly damaged when the model cartwheeled into the ground on a failed bungee launch. I have still decided whether to rebuild the fuselage or scrap the model & use the equipment for a difference design.
5 Sep 99 - After discussing with colleague that assisted me in measuring the fan rpm I have adjusted the figures above. He thinks he had the tachometer set on 5 blades not 7 blades as moulded on the fan. The figures now correlate much better with MotoCalc and seem more reasonable. I am still assessing whether to rebuild the fuselage or not.
13 Nov 99 - I discovered that the wing is also damaged and have therefore decided that it is not practical to rebuild the model due to the extent of the damage. I will now strip the equipment for use in a different model, hmmm.
28 Jun 00 - After I had stripped the model, I had decided to keep the wing, tailplane, fin and canopy of future use. I was looking at them the other day and thought that it wouldn't be too difficult to build a replacement fuselage. Quick as a flash, I have made & covered the keel and rear sections and half finished the forward section. A few more hours with a block of foam, a wire cutter and some film will see the fuselage complete. I will then construct a dolly for use with the bungee, to prevent a repetition of the previous problems.
10 Jul 00 - I managed to get the model repaired in time to take it with me to the BEFA Millennium Bash. I had also made a prototype (wooden) dolly to see if it improved the launching. On Saturday (8 Jul 00) evening I managed to get a test flight in using the new dolly. The bungee was tensioned and the model released by a helper - the launch was superb. The model tracked straight along the ground and gently rose into the air dead level. I will certainly use this system for future models of this type. The test flights were uneventful with the model being rolled and looped with no problem. The only slight annoyance was that the spinner exploded during the initial ground run, probably due to a small crack that had been there for some time. I will have to try and get a replacement.
11 Jul 00 - I re-weighed the model today and the replacement fuselage is currently 6¾ oz. (190g) lighter than the original. However, the model currently has no ducting and this will take up most of the weight reduction.
2 Sep 00 - I have added some information about the launching dolly I'm using to the plans & design section.
25 Mar 01 - Whilst sorting through a load of magazines I came across two flying shots that were published, in Electric Flight International and Radio Control Model World, and decided to add them.