Search results

HomeBuiltAirplanes.com

Help Support HomeBuiltAirplanes.com:

  1. U

    Can we have too much stability?

    I don't agree with you, usually low pitch stability is required to enable large control forces to be applied with managed stick pressures. The pilot must adjust the inputs all the time to maintain a precise flight path. Some owners of aerobatic aircraft will move the battery to the tailpost to...
  2. U

    Can we have too much stability?

    As Billski alluded to stability and control can be a complex subject. In our aircraft pitch can usually be considered on its own roll and yaw have to be taken together. We all know that when cruising along most aircraft will not stay pointed in the same direction for very long without some...
  3. U

    Vashon Ranger Problems

    It is a fallacy that small aircraft get hit by lightning - check the accident statistics, no single engine small aircraft crash because of a lightning strike. Therefore lightning protection is just redundant weight and cost. Can you show the regulation that requires lightning protection for an...
  4. U

    UK IFR panel

    Perhaps your question should be which EFIS can interface with a KN63 (probably most, I think it has a serial output) or a KR-87 (don't know what interfaces this has). The Becker 3500 has a digital interface so may be worth considering, although it is expensive. G3XTouch, AFS 5000 series, Dynon...
  5. U

    Load testing for unknown wing.

    Be careful with the One Design weights. Most come out in the range 900lb to 950lb empty, with some over 950. Very few are under 900lb. With a regular sized pilot, parachute and some gas you could well be over 1150lb. If you are testing I would use at least 1200lb as a typical aerobatic weight...
  6. U

    UK IFR panel

    Well, many people I know are flying illegally! Most have binned their ADFs and use GPS instead. I thought the CAA had already accepted that in practice that was the case? The last time I flew an ADF approach we were 1 mile off the centreline with all the indications were they were supposed to...
  7. U

    UK IFR panel

    Do you really understand the UK rules? No nav eqpt is required for an IMC clearance. Therefore no requirement for certified eqpt for instrument approaches. If you have a certified nav radio (GTN xxx) then anything can be used to display the data, there are no rules governing what can be used...
  8. U

    My foam cutter

    How do you know when the wire is hot enough? Is it a matter of trial and error? If it drags too much turn up the power...?
  9. U

    Full Vinyl wrap?

    Painted first then wrapped to change the colour scheme for airshow work. The main advantages of wrapping over paint is no finishing with vinyl, the ability to change colour scheme quickly and ease of adding complex shapes and accents. Weight depends on the weight of vinyl used against the skill...
  10. U

    Full Vinyl wrap?

    We have recently repaired a wrapped Extra300 at work. I believe it was wrapped to change the colour quickly for airshow work. There were plenty of shapes in the vinyl which we have let the owner match as he has the original wrap design. We found the control surfaces were outside their balance...
  11. U

    Homemade Autopilot with a Raspberry/computer

    Contrasting views are OK. Looks like we will have to agree to disagree. My experience is that if you don't understand the flight dynamics problem you are trying to solve it doesn't matter how good a coder/programmer you are, or how well you understand control theory, the resulting system will...
  12. U

    Homemade Autopilot with a Raspberry/computer

    Bear in mind that the design of an autopilot is a flight dynamics, not a computing, problem. Once you have the flight dynamics solved the computing aspects will be straight forward. If the flight dynamics are ignored it will never work well. - You should have 'inner' and 'outer' control loops. -...
  13. U

    Putting a tapered wing on an RV

    Actually the same wings used on a 7 and an 8, as the fuselage is wider the 7 has a slightly longer span. Yes, the larger rudder was to improve spin recovery handling. The 4 & 6 have non-counterweighted rudders where as the 8 & 7 have counter weights. The 9 has significantly longer wings so...
  14. U

    Polyurethane bushes for suspension

    As each wheel has 2 suspension legs I wonder if one leg could be the spring and the other the damper? The properties of a PU stack seem straight forward to tailor, even if I can't say right now what properties I require. I believe some motorcycles do this with their front forks. It may well take...
  15. U

    Polyurethane bushes for suspension

    Thanks for replies. Yes, damping as well as suspension, although there may be space for a small conventional damper above or below the PU stack, depends how tall stack needs to be. Interesting that the McM-C table says the longer the bush the lower the permissible load.
  16. U

    Polyurethane bushes for suspension

    I'm considering a design that uses coil springs in compression for suspension with the coils housed inside 2 sliding steel tubes, similar to a Chilton DW1A. http://www.chilton-aircraft.co.uk/Images/113.jpg http://www.chilton-aircraft.co.uk/Images/mis10.jpg It struck me the other day that a stack...
  17. U

    80% Scale Hawker Hurricane

    I guess everyone is familiar with this Hurricane? SSDR Hurricane Presentation
  18. U

    Putting a tapered wing on an RV

    How did you roll the leading edges?
  19. U

    Putting a tapered wing on an RV

    RV-6 wing root design. The RV-6 wing root design is very different to the RV-8. It is similar to the RV-4 with a built up laminated spar (from 0.24" x 1.5" 2024-T3 strip), but the SBS fuselage means the bolted portion is longer. The central part of the spar has 4 x 0.25" strips plus one 0.125"...
  20. U

    How does this wing work?

    Its all about the rules and trying to maximize performance within a quite prescriptive rule set. The wing is often slightly flexible - I suppose to reduce drag at high speed. Bear in mind that a new wing shape is often used for each individual track. At high speed track only a couple of elements...
Top