Kansas City Radio Control Association AMA Charter No. 390 CONTACTS. The Official Newsletter of KCRC

Transcription

1 Kansas City Radio Control Association AMA Charter No. 390 CONTACTS The Official Newsletter of KCRC March 2016 Volume LXII, Issue III Training Returns to Charles Reed Flying Field in May I was at field on Saturday March 4 th and what a beautiful day it was for flying. It looks like Spring may have arrive early this year. The wind was mild and out of the Northwest and occasionally out of the West. Even with the crosswind we had one young man make his first solo flight (see Page 7), and I gave new student Chuck Jones his first flight on the buddy box. The training going on got me thinking that I should update everyone on KCRC s training program. Training Night will be Tuesday evenings starting in May. If you are a new or returning student you will be paired with a qualified flight instructor. If you have never flown before we will spend some time talking about the basic of flight and how your airplane works. Once that is completed we will start you off with some basic flying in straight and level flight, and then slowly working in to turns, take offs, and lastly landings. If you were at our training last year then you can just pick up were you left off with the instructors. The Club does have several trainer aircraft available, and will need to be shared among students that do not yet have their own plane. If you do have your own plane please bring it along and we can help you set it up for basic flight. Continued on Page 2 IN THIS ISSUE Training Night Returns in May Page 1 Officers and 2016 Event Schedule Page 2 Minutes of the January Club Mtg Page 3 Photos From Yesteryear Page 4 Alan Brown Article on Tails Page 5 & 6 Seen at the Field Photos Page 7 Craig White Helping New Student Pilot, Chuck Jones Joe Briaullt and Edge Don t miss the March Club Meeting Wednesday the 16 th at the EAA Hanger Lee s Summit Airport Jimmy C & Smoothy

2 CONTACTS PAGE 2 There are a number of other important support items you will need if you have your own airplane and it is ready to fly with the radio system s batteries charged overnight. These might include fuel, a glow plug ignitor, and electric starter (optional. You do not need to be a member of KCRC to participate in the training program. However it is a requirement of Jackson County Parks and Recreation that every pilot have an RC Park permit. To obtain an RC park permit go to the park administration office located at the intersection Woods Chapel road and Liggett road. The cost of the permit is $25.00 and is good until December 31, You will need to present your AMA membership card at the time you get your park permit. Hope to see you at the field! President Craig White There is no Safety Article This Month because Susan Calvin s Mom is very ill and requiring a lot of Susan s time. Keep Susan and her Mom in your thoughts and prayers! APRIL 20 TH CLUB MEETING WINTER PROJECTS SHOW AND TELL This will be a time for all you KCRCers to show off the new airplanes you have been working on during those long Winter Nights! KCRC 2016 Schedule of Events (Remaining) April 30 May 1 Quickie Race (Club help needed) July 23 3-D Poker Fun Fly August 13 National Model Aviation Day September 10 Warbird Fun Fly Flight Training Nights will again be available every Tuesday evening, beginning May 3 rd. Club Meetings are held monthly on the 3 rd Wednesday at the EAA Hanger at the Lee s Summit Airport. From May through August Club Meetings will be held at the flying field. Your 2016 Officers Craig White, President kcrcpilot@gmail.com Duane Hulen, Vice-Pres drhulen@sbcglobal.net Tom Safley, Treasurer (816) tomsharsafley@sbcglobal.net John Midgorden, Secretary (816) jomidgorden@me.com Your Board Members Susan Calvin (816) Scalvin47@earthlink.net Gary Fisher (816) garyfisher@earthlink.net Fleming Park Liaison & AMA District VI Representative Jim Cianciolo kcrcpilot@comcast.net Newsletter editor John Midgorden (816) jomidgorden@me.com 2016 Membership stands at 60

3 CONTACTS PAGE 3 MINUTES OF THE FEBRUARY CLUB MEETING The February 16 th KCRC club meeting, held in the EAA Hanger at the Lee s Summit Airport, was called to order by President Craig White at 6:50 P.M. The other officers present were Treasurer Tom Safley, Vice-President Duane Hulen and Secretary John Midgorden. There were twenty-four members present, including the officers. OFFICER REPORTS President Craig White opened the meeting with the sad news of Joe Cygan s death earlier in the day. He read an obituary ed to him by a member of the family. A discussion followed as to whether to send flowers or support one of Joe s charities. It as agreed to send $100 to one of the charities mentioned in the obituary. Tom Safely will take care of this. Craig asked for a motion to approve the minutes of the January meeting, Motion accepted and approved. Secretary John Midgorden indicated that based on renewals during this meeting the 2016 membership is now 59. He also announced that February 19 th is the deadline for the FAA Registration. John also brought to everyones attention that Ron Dulinsky has a photo of his modified electric powered SIG Kadet in the latest Model Aviation Magazine on the Focal Point page. Vice-President Duane Hulen had nothing to share at this point in the meeting. Treasurer Tom Safely reported the Club is still solvent and shared the checking account balance. The Appreciation Dinner expenses, including a stipend to the guest speaker, ended up at $772. Tom summarized the Swap-N-Shop event income. Although table sales were down some, they more than paid the rent. The Club made money on the raffle. Bottom line is the club cleared a little over $1,800. Tom indicated the event was a success, even if the income was down somewhat from previous years. Tom recommended that Club tie down the John Knox Pavilion for next year. Duane indicated he would follow up on this request. Parks Jim Cianciolo shared more information about Joe s funeral service. Jim also shared that there will be combined AMA leadership meeting in Lenexa, KS on the weekend coming up. Randy Cameron will have a round table discussion. Jim will report back on the meeting. Jim has turned in events schedule to the Park. Carey Minor mentioned there will be two control line combat events (similar to last year) which he needs to get scheduled. Jim mentioned that he brought copies of a volunteer hours form that needs to filled out and given to the park before they will honor volunteer hours. Jim shared that he had sent an to the Park with a list of items that need to be addressed. They include gravel for pot holes in entrance drive, moles, restroom situation, and dogs in flight area. OLD BUSINESS Susan has the AMA sanction for her September Warbird event. NEW BUSINESS Craig wondered who would be the CD for the 3-D event. There was an assumption that Barb Carey had agreed to do this again (this needs to be verified). Duane Hulen mentioned that he has ordered fuel for the Quickie event. He would like a check from the Club. Gary Fisher moved we give Duane money for the fuel he has ordered. Motion passed. Duane also indicated that for next years Swap-N- Shop event there needs to be a closing time indicated in the PR release. He also pointed out the need for chairs at the tables for the sellers. There is also a problem of people putting large airplanes on the floor. Some events like this at other clubs charge a floor fee. This needs to be explored for next year. It was announced that Jim Koch will be having his surgery on this coming Friday. Darwin Ulledahl talked about the need to improved the control line area. Specifically making it more level. Jim Cianciolo recommended that a plan be developed and submitted to the Park for their action. PROGRAM A segment of a video of the Oshkosh 2015 event was previewed, thanks to a neighbor of John Midgorden, who loaned him the DVD. Respectively submitted, John Midgorden, Secretary

4 CONTACTS PAGE 4 PICTURES FROM YESTERYEAR John Midgorden s Hotdogger (circa 1979) Blue Ridge Mall Show (Hulen s T-28?) Charley Reed and Flying Lawnmower Tom Cook s F-4 Phantom Ducted Fan Anyone Recognize These Guys? Looks Like Fred Hulen Helping a Youngster

5 CONTACTS PAGE 5 HORIZONTAL TAILS Let s look at how tails work and then see if we can explain some of the phenomena that we might observe at the flying field. Let s start with a very conventional and stable layout - a high-wing airplane with a flat-bottomed wing section and a tailplane at a smaller angle of incidence with a symmetrical airfoil section. It looks something like this. The wing is at a big enough incidence that it can lift the weight of the model in level flight. The tail is sitting at zero incidence and so isn t contributing any lift. It may even be contributing some negative lift because of downwash from the wing, but let s neglect this for the moment. As the wing center of pressure (or center of lift) acts at about the 25% chord point, then in order to balance, the c.g. will also be at 25%. Now imagine that the airplane pitches nose up for some reason. The wing generates a little more lift, which will cause the airplane to rise somewhat, but it s still at 25%, so it won t pitch the airplane. The tail, however, now has some positive lift, which makes the airplane rotate nose down, getting it back to where it started. Conversely, if the airplane pitches nose down, the tail produces negative lift and pitches the airplane nose up. Clearly the airplane is stable in pitch. Now I want to differentiate between center of pressure and aerodynamic center. These are sometimes used interchangeably in the model airplane press, but that s not correct. The center of pressure is the point where the net lift of the airplane acts and in steady level flight has to be at the same place as the c.g. of the airplane. Center of pressure a Aerodynamic center b a = n x tail area where n is less than one b wing area BY ALAN BROWN However, if we rotate the airplane to a new angle of attack (incidence angle is how we rig the airplane, angle of attack is the angle the airplane presents to the airflow at any point in time), then we ll get some incremental lift from the wing acting at its own center of pressure and some from the horizontal tail at its own center of pressure. The extra lift will act somewhere between the wing and the tail at the aerodynamic center. That point will be given by the ratio of tail area to wing area multiplied by a coefficient less than one, as shown in the illustration. The coefficient will depend on the aspect ratios of the two surfaces and the downwash from the wing. The smaller the ratio between tail aspect ratio and wing aspect ratio, and the greater the wing downwash at the tail, the smaller will be this coefficient. Depending on how we set the initial tail angle, we can obviously have the tail, at normal flight speed, either help to lift the airplane or give negative lift. In the former case, the c.g. will be aft of the 25% chord point, and in the latter case it will be forward of the 25% point. The position of the aerodynamic center, however, does not change. Suppose we trimmed the airplane with the c.g. right at the aerodynamic center, then the airplane would be neutrally stable (there d be no pitching moment relative to the c.g.), but conversely we wouldn t need any change of trim to fly faster or slower. Any small elevator movement would result in a rapid response because the extra wing lift acting at its own center of pressure gives a very strong pitching moment. So, as we all know, moving the c.g. back allows us to trade maneuverability for stability, or allows us to have smaller control surfaces, but still with lower stability. The reverse happens if we trim with the c.g. forward of the 25% point. Continued on Page 6 Jim Koch still hasn t had his surgery due to a lingering infection! Keep Jim in your thoughts and prayers!

6 CONTACTS PAGE 6 TAILS (CONTINUED) If we fly the airplane a bit faster, it will need a smaller wing angle of attack, which results in a negative tail angle. We ll have to add some down elevator to keep the airplane trimmed, otherwise it will want to pitch up. Conversely, if we want to fly more slowly, we have to add up elevator to keep trimmed. For simplicity I haven t included the effects of thrust line position and the increased or decreased thrust required to maintain the speed we want. Now let s look at what happens when we get to the stall. The wing now loses lift at some specific angle depending on its aspect ratio. If the tail has a lower aspect ratio, then it will stall at a higher angle and so should keep on lifting after the wing s lift is falling off. This is good news because the airplane will be super stable in the stalled configuration. The tail s angle of attack isn t completely obvious because it is affected by the wing s flow field. If it is fairly close to the wing, then the flow field will be affected by the downwash and the tail will act as if it has a lower angle of attack than it really has. However, suppose the tail is several chord lengths behind the wing and has a higher aspect ratio than the wing. Now it will stall before the wing stalls, and the airplane will have a dramatic pitch up near the stall (translation: on landing approach!).. so now we know how to avoid low speed pitch up. Keep the tail aspect ratio substantially less than that of the wing. But suppose we have a canard airplane. These aircraft are noted for their forgiving stall characteristics, because the canard is trimmed at a slightly higher angle than the wing and so will stall first, allowing the airplane to drop its nose before the main wing stalls. However, if we put a conventional low aspect ratio tail surface at the front end it will keep lifting after the main (high aspect ratio) wing has stalled. Bingo, we re back to pitch up on the approach. This is why most self-respecting canard aircraft have BY ALAN BROWN higher aspect ratio canard surfaces than the main wings. So the rule now becomes, regardless of the relative sizes of the front and back surfaces (canard, tandem or conventional tail), the front surface should have higher aspect ratio than the rear one to avoid low speed pitch up. Swept wings are not more prone to wing tip stall than straight wings. It just seems that way because they often have higher taper ratios. However, if a swept wing does stall at the wing tips first, then this is just like a tail stalling before the main wing - low speed pitch up. So the effects of tip stall on a swept back wing are more dramatic than for a straight wing. Conversely, a swept forward wing is almost guaranteed not to pitch up if the tips stall first. It s thus no surprise that the X-31 research aircraft designed to research post-stall characteristics has swept forward wings. One more thing. Despite the tendency of low aspect ratio surfaces to stall at higher angles of attack, we can still screw things up by putting a horrible airfoil section on them so that they will get flow separation at a fairly low angle of attack. A good example would be a tail made of 1/4" sheet balsa with absolutely no leading edge streamlining. This again becomes an airplane asking for drastic pitch instability at low speeds, particularly if it s teamed with a very fat wing which will not tend to have premature flow separation. We have probably all seen examples of model airplanes with these very scary characteristics. I hope you enjoy this article from my California friend, Alan Brown. As you may remember Alan worked for the Lockheed Skunk Works and was the project engineer on the F-117 Stealth Fighter. Editor CHECK OUT THIS WEBSITE ABOUT TRIPLE TREE AERODROME THAT INCLUDES THE JOE NALL EVENT WT.mc_id=160304epilot&WT.mc_sect=trp

7 CONTACTS PAGE 7 Braden McNeill After Solo Flight (Proud Dad) Rob Weesner and His Big Gasser Craig White Preflighting his 60 Size Trainer Mike Ryken Adjusting Quickie Stab THIS 100 DRONE SYNCHRONIZED AIRSHOW IS THE WORLD'S LARGEST AND MOST IMPRESSIVE - 2 Min, 25 Sec Drones have a lot of people worried about privacy, but they can be used for good as well as nefarious purposes. Take, for instance, a spectacular display of drone technology by Intel Corporation (USA) involving 100 small aircrafts being launched skywards in formation has earned a new Guinness World Record for the Most Unmanned Aerial Vehicles (UAVs) airborne simultaneously. Controlled on the ground by a crew using PCs with Intel software, the mass of drones lit up the night sky in sync to a live performance of Beethoven s Fifth Symphony and executed a stunning light show resembling a fireworks display. Drone 100 took place at Flugplatz Ahrenlohe, Tornesch, Germany, in November The record was set in collaboration with Ars Electronica Futurelab to push the limits of the UAV industry and to show what UAVs can be used for.

8 CONTACTS PAGE 8 An Exciting New Father-Son Team CLUB MEETING February 16 th 7:00 P.M. Club Meeting in the EAA Hanger at the Lee s Summit Airport Meet Our New Club Members, Scott and Braden McNeill FEBRUARY CLUB MEETING PROGRAM More Highlights of Oshkosh 2015 CONTACTS KCRC E. 29th Street S Independence, MO March 2016 Volume LXII, Issue III MAIL TO: