ELECTRIC FLIGHT U.K. - British Electric Flight Association

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A word of warning, if you are not confident in your engineering skills do not attempt to mess about with home made propeller hubs, for safety’s sake. You can contact me by email at dfamstanley@onetel.com (Editor: As I have some of the Ramoser varioPROP units, I thought I’d check one out. I took an 8B hub and 9.7” scale optic blades and set it mid-range at 6” pitch, which I thought would be the pitch the blades were optimised for. I measured the blade pitch angles and graphed the result, shown below.) 40 E.F.-U.K.
A year of Flying with LiPo By Malcolm Mackendrick I have been flying electric powered models for about 8 years now and going totally electric about 5 years ago. I've also replaced the brushed motors with brushless in 14 of 19 of my models. After the introduction of Li-Ion then LiPo batteries I read everything but did not plunge in as I had a considerable investment in NiCd and NiMH batteries and 4 good chargers. I could go flying all day and until my lead acid batteries were down could charge up batteries faster than I could fly them flat!! Last year as several of my packs were in need of replacement, I bit the bullet and bought two 3S1P 1600mAh and a carbon backed 3S2P 3200mAh pack from <strong>Flight</strong>power. (Editor: BEFA have told <strong>Flight</strong>power on a several occasions about the risks of putting LiPo cells in a conductive, flammable cladding. If the pack does catch fire, it just adds fuel, and dangerous pollutants, to the flames.) The first aircraft flown with these packs were those where the CG variation by lighter pack usage did not change. My Crossfire which has an AXi 2814/10 was transformed to near vertical climb and about 14 minutes flying time. (I set timers for all aircraft leaving a reserve. The Crossfire is set at 10 minutes) My first charger was a Kokam basic giving up to 1.5A but very easy to use. I did not try and set up my Chameleon chargers for LiPo. Firstly I found programming it difficult and as I was using them to charge NiCds I had them on auto charge for that and couldn't rely on not having a "Senior Moment". All my battery purchases in the last few months have been of the same LiPo packs except that with 2 carbon cased 3S2P packs I decided that the extra 30g was undesirable. I now wire up all my aircraft to take as many packs in parallel as is needed for the output amperage required. For Example my Vasa ducted fan tailless jet uses 2 of the 3S1P packs. My biggest model with an AXi 4120/18 which used to use 16 cells of 3000mAh NiMH drawing about 45A and driving a 14" x 9" propeller, now has 2 of the 3S2P packs in series in parallel with another 2 of the 3S1P packs in series, making the final formula 6S3P giving about 24v. I have had to prop down to a 13½" x 7" to get down to the recommended 40A for the motor. Again the flying has been transformed by the weight reduction, increase in power and best thing safe flying time has gone up from 5-6 minutes to 10. Earlier this year I bought an Astro Lithium charger and test discharged all my packs to see what capacities they had. Only one was down, this pack had been in a full vertical dive crash and was somewhat "crumpled", with it's capacity now was down from 1600mAh to about 500mAh. The voltage was still normal and I had flown it for about 3 months albeit being aware of reduced performance. E.F.-U.K. 41
Page 1 and 2: ELECTRIC FLIGHT U.K. ISSUE No. 81 S
Page 3 and 4: Electric Flight - U.K. Issue 81 - S
Page 5 and 6: Chairman’s Chatter Dear members,
Page 7 and 8: You probably heard through the grap
Page 9 and 10: Right is shown the Reichard Sprinte
Page 11 and 12: Left: are the latest enhancement to
Page 13 and 14: Readers’ Models Your chance to sh
Page 15 and 16: The Hornisse away! Chris with his M
Page 17 and 18: A gentle flare, note the Fowler fla
Page 19 and 20: E.F.-U.K. 19
Page 21 and 22: 1) The battery pack of 9 Sanyo 800A
Page 23 and 24: the model was coming towards me. I
Page 25 and 26: Blackpool & Fylde Electric Day by J
Page 27 and 28: E.F.-U.K. 27
Page 29 and 30: E.F.-U.K. 29
Page 31 and 32: Oil get it done quickly! The origin
Page 33 and 34: higher than I could have achieved i
Page 35 and 36: touched down "on the numbers" and r
Page 37 and 38: Variable Pitch Propellers by Don St
Page 39: The collected results are shown plo
Page 43 and 44: safely accept 1.6A putting several
Page 45 and 46: Inside the hall E.F.-U.K. 45
Page 47 and 48: A Protech Ultimate hovering in fron
Page 49 and 50: The motor used is a double ended Tw
Page 51 and 52: John flying the completed CH-47 The
Page 53 and 54: The Lama uses contra-rotating rotor
Page 55 and 56: The 51st Toledo RC Exposition by Ra
Page 57 and 58: The LCD readout is mounted on your
Page 59 and 60: esults to your printer for hard cop
Page 61 and 62: Even using the ply, we can shave so
Page 63 and 64: Move servos, battery, and even the
Page 65 and 66: July 2005 (continued) 10th You are
Page 67 and 68: October 2005 2nd Unlimited Scale Co
Page 69 and 70: New to ELECTRIC FLIGHT? START HERE
Page 71: FANS Morley ‘Jet Elec’ Fan ....

ELECTRIC FLIGHT U.K. - British Electric Flight Association

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