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PatMc

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PatMc last won the day on September 8 2021

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  1. Re SLEC, is this acceptable evidence ? Quote : "The company still produces a good range of accessories but also a large range of quality balsa wood sheet & strips, hardwoods all machined in our mill at Watton." Source : https://www.slecuk.com/index.php?route=information/information&information_id=4
  2. PatMc

    Electric Cars.

    Paul, you're becoming repetitively tedious.
  3. Sorry Andy but I don't think that addresses my response or Simon's reasoning. The thrust line will remain through the same place wrt drag no matter what the power changes are made.
  4. Actually what I'm saying is that the tailplane isn't necessarily parallel to the ground when the aircraft is in flight also the wing incidence isn't necessarily the angle that the wing presents to the air (Angle of Attack) it's penetrating. Considering an aircraft in steady straight and level flight - since the thrust line is tied to the wing incidence any change in AofA during flight causes the same change to the thrust line - i.e. the thrust line angle alters depending on airspeed. All this boils down to remembering that the thrust line, wing & tailplane incidences and any datum line shown on a plan are no more than rigging references.
  5. Simon, if that's the case then why isn't it a common feature in full size high wing aircraft ? Also why do some scale models incorporate down thrust that isn't in the aircraft being portrayed ?
  6. The options you mention are exact opposites. The combination will just cancel each other out but the model will fly tail down for the model to achieve the same angle of attack at any given airspeed. The thrust line and wing incidence are fixed with respect to each other. If extra down thrust is applied the angle between the two increases, if the thrust line isn't altered but the incidence is reduced obviously the angle between them also reduces.
  7. What makes you think that the thust-line is parallel to the tailplane ? Free flight designs were not hand launched due to marginal power. In fact they were often launched from the ground (ROG). However there was (still is) sometimes other reasons to hand launch them, e.g. they had no rudder control to keep them on course, if it's difficult to keep them heading into wind or a bit too gusty hand launching is more practical. Bear in mind what are now vintage FF models were not designed by vintage modelers, many of them were not meant to trundle round in the manner we're used to seeing today. Back in the 1950's it was reckoned that most FF duration models could climb as fast as a Spitfire.
  8. Full size aircraft are designed by professionals who have access to wind tunnels & measuring equipment then have the prototypes proved by professional test pilots etc etc before any production aircraft are approved. Model aircraft designers, except for a very few, don't really "design" their models. They generally copy previous model's features into their own using the TLAR &/or cut 'n try methods. They are also prone to accepting hangover features from free flight & restricted RC systems of the past without thinking that perhaps those features are no longer necessary when we have full proportional control available. Nothing wrong with using rudder deflection, it's easier to adjust than engine deflection, in fact many full size have the fin & rudder offset built in
  9. Even - quote "Yesterday it was looping (or attempting to) at all throttle settings - of course at the lower throttle there wasn’t enough power for it to complete the loop, so it would pitch up violently and then stall, recover, rinse and repeat." ?
  10. It could be a John Hancock designed Halcyon - RM 118. What span is it ? The Halcyon was 110" very lightweight, IIRC about 5 or 6oz/sq ft - too light actually for most competitions back in the day.
  11. PatMc

    Electric Cars.

    Tim, governments (of all nationalities & political persuasion) never lack imagination when they think of criteria on which to levy tax.
  12. It's not uncommon on full size aircraft whereas side thrust is very uncommon.
  13. The Junior 60 doesn't need any side or down thrust. Any tendency to turn is easily catered for by rudder trim, throttle control takes care of rate of climb & speed when combined with elevator trim. Mine has no side thrust but does have several degrees of built in down thrust only because I didn't know any better when I built it around 1987.
  14. There's actually no such thing as a specific fixed thrust angle unless if it's taken with respect to some other horizontal or near horizontal straight line (e.g the wing's angle of incidence). No matter what is taken as the reference the thrust angle will be changing with every change in fore & aft trim.
  15. If it's the same position cell on both batteries it could be that one of the chargers is reading that particular balance position lower voltage than it really is causing the cell to be overcharged when attempting to balance it. This once happened to me, banjaxed 3 or 4 batteries before I realised the problem.
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