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Peter Jenkins

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Peter Jenkins last won the day on March 1 2023

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  1. By the time I arrived at the patch, it was 2.30 pm and everyone else had left. Had 3 practices of my schedule and tried a lower level flight speed. Decided that the faster speed gave a better pace to the flight so that's sorted. Might have to try a faster speed for really windy days as I seem to have the flight pack capacity to achieve that. With the 4,800 mAh Onbo packs I've been using they get down to 3.7 v/cell at the end of the schedule. I tried a 5,200 mAh Onbo and as I mentioned above a 5,200 mAh Roaring Top. I was impressed with the Roaring Top so bought 2 more. After checking how much went into the 3 Roaring Top packs it varied from 3,000 to 3,200 mAh so around 2,000 mAh so I could safely budget on burning up to 1,000 mAh more per flight on windy days.3👍
  2. Well that's blown your secret Bob!🤣
  3. One of the top UK F3A team pilots flies like that. It's what ever works for you and that enables you to fly to your required standard.
  4. Hi Toto I've appended some photos of my Wot 4 that I used to gain my B and that I still fly from time to time to demonstrate the B to candidates. I should say that I arrived at these, and the current CG, through a process of trial and error over the 3 months that I spent practicing for my B. I have since measured them and they are quite instructive. On my Tx I have 3 rates as normal and I used them for spinning (max control movement), normal flying and flying the 2 consecutive rolls that require a constant roll rate as one of the criteria. Starting with the ailerons, the photos show the full rate movement, then the normal rate and then the 2 continuous roll movement. In the last case, I chose this rate so I could apply full aileron and then just have to worry about timing the elevator inputs since there isn't a requirement to use the rudder for these rolls. Out of curiosity, I have flown the entire B schedule, excepting the Spin, on the lowest rates and it is perfectly doable but you do need to use full aileron for rolling into and out of turns, and full elevator for the loop and bunt. 18 degrees 10 degrees 5 degrees The Elevators follow: 18 degrees 10 degrees 5 degrees It won't have escaped your notice that 10 degrees of movement are what I arrived at through trial and error. Now, I set these figures as my starting normal flying control throws and adjust from there. Note that even with just 5 degrees of movement with full stick movement is sufficient to fly the B schedule manoeuvres but you do need to make sure that you are high enough for the bunt! The height required is just a bit higher than the top of the loop! This may not be the case for other aircraft or if the CG isn't in the optimised position. Hope that helps. 100 60 30
  5. Yes, but Toto doesn't have your experience. In any event, in my experience, the majority of pilots in their early stages tend to having too much movement on the controls that leads to problems of over controlling and pilot induced oscillations that usually end badly. I will post some photos for Toto's benefit.
  6. Toto If you have a throw meter there is no need to calculate the angle. Just use the throw meter. I didn't realise you had the throw meter hence the trigonometry lesson. Ron, it's all dad simple trig. The issue is how to get the functions on a calculator.
  7. At the point they tell you to measure the control throws Toto, what is the chord if the control surface. Then divide the throw, in this case 22 by the chord, or width of the ckntrol surface, lets say it's 100 mm to make the sums easy. So 22÷100= 0.22. Now on your mobile select calculator and turn the phone so it's in landscape mode and you'll get the scientific calculator. I've taken a screen shot of my Samsung phone calculator and attached it. Kn the screen shot at top left there are 2 horizontal arrows that trigger between normal and inverse function. You may remember that in a right angled triangle, tangent is the legth of the vertical side opposite the angle in question and adjacent is the side forming one arm of the angle. So your 22 mm is the "opposite" side and the chord is the "adjacent" side. The division I gave in two paras above gives you the tangent of the angle. Now, if you press that button with the two horizontal arrows going in opposite directions you will see the Tan button changes to Tan-1 except the -1 is small type and raised to the top as in my screen shot. This function now gives you the angle of the measurements you have input. So, in my example, the answer is 12.4.deg. if you are much higher than that for your rate that you are using (not 100%) then you need to bring it back to between 10 and 15 degs. It's more useful to talk about degrees of throw than measuring at a specific point. You csn use a throw meter (something like this https://www.aliexpress.com/item/1005004102469102.html?pdp_npi=4%40dis!GBP!17.39!13.22!!!156.41!118.87!%40210126da17189344561877705d13d3!12000028039512071!affd!!!&dp=50244fd6546b151505bbab1b066288639b80e47a&aff_fcid=e758a52542ee4f23bde22d5f6050ae38-1719167898106-09315&aff_fsk&aff_platform=api-new-product-query&sk&aff_trace_key=e758a52542ee4f23bde22d5f6050ae38-1719167898106-09315&terminal_id=822bf8e54f304dc78ba66515f44fefa7&afSmartRedirect=y) to give you the measurement directly. You can now compare control throws on different size control surfaces, or models, very easily as an angle is absolute. Hope thst helps.
  8. Possible causes of the Beaver problems: 1. CG too far aft - move it forward by 5% of wjng chord. 2. Too much control movement for the size of the control surfaces - reduce the throws to 10 degs for aileron and elevators and 25 degs for rudder and try that. Peter
  9. I started flying using a neck strap and thumbs and that took me past my B test onto competition aerobatics. However, when I had long, half the length of the box long, inverted flight, I struggled with holding the right amount of elevator so when someone suggested a tray I thought I'd give it a go. In the end, it took me 3 months to get back to the standard I had been at flying thumbs. It initially felt alien but I gradually got used to it. If you are planning to make the move then best to fly regularly till you get used to the tray. The benefits as far as I was concerned were that: when I got tense, I would tilt the Tx towards me and cramp my thumb movements. With the tray, and using the pinch technique, as I wasn't holding the Tx I could not tilt it towards me so that removed that issue. with the tray, I could take both hands off the sticks and give them a shake before re-engaging with flying. Helped to reduce stress. inverted flying was now much easier to achieve since with the hand rests I could just keep my wrist anchored and gently move just thumb and finger. It led to a huge improvement in my ability to fly long level inverted sections. I do occasionally fly thumbs only but I don't feel like I can fly with the same precision as when using a tray and pinch technique. The Tx is protected from ground contact when in the tray so helps to keep it dry and cleaner. Finally, I use a harness that sits on my shoulders and this has stopped the neck ache I used to get with a strap holding the tray in place. I would thoroughly recommend taking the time to get used to the different feel of flying with a tray and using a neck strap and thumbs or just holding the Tx. Having said that, Andrew Jesky who came 2nd in the world aerobatic championships last September doesn't use a neck strat, holds his Tx in his hands and flies thumb and finger using other fingers to operate a number of switches for various flight conditions. He usually has his arms hanging straight down with the aerial pointing down at the ground. Then again, he's an exceptional pilot!
  10. Didn't have a very good competition last Saturday. The Anthem got blown over just as I was about to start my 2nd flight take off. Smashed both props, the spinner and grazed the top of the port and underside of the starboard wing tips but the real issue was 3 of the 4 hinges on the rudder were broken! I had spare props, spinners but no spare hinges! All rather trying! Today (Sat 22nd), having repaired the damage and replaced the mylar hinges with Dubro pin hinges, the Anthem was back in the air at my second Club site. I had wondered if rudder trim had changed with the new hinges and, by golly, it had! I had 9 clicks of left rudder before she flew straight! So, 3/4 of a turn on the rudder turnbuckle (love turnbuckle rods) and I could dispense with the rudder trim. Also christened 2 new Roaring Top packs (2 x 5S in series to give 10S) and found that they appeared to have more remaining after the schedule than the original one that had prompted me to buy more of the same. As the new ones are a tad wider and heavier I do wonder if the original pack that I bought really did have the 5,200 capacity it advertises! Although I had to stop for a rain shower for 15 mins, my trusty ground sheet kept the aircraft dry and the rest of the stuff got slung into the car boot till the rain passed. Still, managed to have 5 flights, all P25 schedules in the 2.5 hrs I had at the field. I should add, that I was on my own until to mins before I left.
  11. Ah, well done on working that out. Do you fly thumbs? After I started flying in aerobatic competitions I found flying thumbs was not so good for me. When I got tense I tilted the Tx towards my body and cramped my thumb movements. Moving to a tray took me a couple of months to get used to it and flying with finger and thumb but after that it's been an absolute boon. I still occasionally use thumbs to fly but it just doesn't feel as comfortable nor as accurate to me. It is very easy to apply right aileron whdn you pull up to loop or push down to bunt because of the geometry of a thumbs movemsnt when holding the tranny - as you have found. If you suffer from neck ache when using a neck strap there are shoulder harnesses that overcome that problem. There are specialist ones (Revoc for one) but some camera shops might also have something suitable. I also found that when I got tense, I could just let go of the tranny, without it wobbling around to stretch my hands and arms when the aircraft was flying S&L between a msnoeuvre at box edge and one in the crntre. Another huge help was being able to use the wrist supports to brace my hand when flying a long inverted section where the aircraft needs to be dead level. Switch operation is also, for me, much easier - I don't need the sliders on the back or side of the Tx for my flying so that's not an issue for me.
  12. Unfortunately Chris, that falls into the necessary but insufficient category. You need both to set the required deflection to be the same but also to have the servos moving in synch with each other over the whole range of movement that you set. I have been flying in F3A competition since 2011 and the FAI Preliminary schedule since 2015 - not as well as I would like! - so I am well aware of what is required as regards trimming and the techniques used. The photo shows that once I've used my throw meter to set, in this case the elevator throw for normal aerobatics - I generally start at 10 deg each way and then reduce as necessary - the next task is to ensure that the 2 elevator servos move together over their entire range. I use a pair of new pencils (hexagonal cross section and not round) having first checked that their points align when both are placed flat on a horizontal surface. I then tape them to the elevators as in the photo. (You may need a gap to clear the rudder if either the pencils are too short or the rudder extends aft too far.) You can either use a mix between the two elevators or your Tx might have an elevator balance function. Then it's a matter of adjusting the slaved servo to ensure the pencil points remained aligned throughout the range of movement. Of course, this is less easy with ailerons but at least ensuring both have the same deflection is a start. Then, make up a jig that can be taped to the wing adjacent to each aileron that holds a graduated scale and do the same exercise as for the elevators. Remember, for a single prop aircraft, the roll rate with torque will be faster than sgainst torque for the same aileron deflection. If you use a contra rotating prop setup then you won't get this problem. In reality, you may not even be aware of the slight difference in roll rate.
  13. When I was practicing for my B, I set up an aileron rate that with full stick deflection gave a rate of roll that I could time my elevator inputs with accurately. Some time later, I mentioned that I had a roll rate of almost 2 secs and I was told the this was a slow roll. So, I went away and decided to check the roll rate. Quite surprisingly, I found that rolling to port, i.e. with the engine torque, the roll rate as half a second faster than when rolling against torque. This wasn't noticeable until I timed it. The other issue is that the ailerons might be moving at different rates even though the end deflections are identical. On my F3A aircraft, even using expensive servos, I have to use the elevator balance function to get both elevator servos to move the elevators the same amount. It is quite surprising how even expensive servos need this trimming. The same goes for the ailerons and since they are not as easy to measure you will need to make up some card templates with the degrees or some other interval marked off and check that they deflect the same amount for the same stick movement. This is sometimes referred to as differential but it isn't the same differential to which we refer when talking the aerodynamics of ailerons. This differential is to get the ailerons to move exactly the same amount, in opposition of course. If there is a significant mismatch on right stick then that would cause the corkscrewing you are experiencing caused by the big difference in drag that may be being generated by mismatched aileron movement.
  14. Never lost a comp screw but then I had a Mills 75, PAW 249 and more recently a PAW 149. Never used a comp screw lock nut either. Perhaps I was lucky.
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