Hi Dennis:
Both of my Crossfire Extremes (the tail-dragger and the trike version) fly very well and there is little between them to make one preferable to the other when it comes to the flight maneuvers. The decision to use the trike version was because of the ground handling virtues of that ship. Takeoffs and landings are very easy with that ship, even in high wind conditions. I received a lot of big numbers from all of the Nats judges on those maneuvers with the new ship and I think that is significant. I don't understand why more fliers don't opt for trike gear. I do know that the placement of the main gear relative to the CG is very important, as is the angle at which the ship set on the ground. The main gear must not be positioned too far aft of the CG (with battery on board) or the tendency will be for the ship to abruptly hop into the air. You must be able to raise the nose gear and let the ship run on the main gear and then lift off at a low angle to get max points. The ship must also not set at a nose down attitude. I wish I could tell you that I adjusted and trimmed the new ship's landing gear geometry to get it perfect, but the truth is that I hit it perfect right off the board. Dumb luck on my part to be sure...
The new ship has a longer nose to allow me to use a lighter battery placed more forward to achieve the proper balance point. That worked out perfectly. The older ship uses a 4,000 mAh 4S battery that weighs in the 14 ounce range and the new ship uses a 3,300 mAh 4S battery that weighs around 12 ounces. With the addition of the nose wheel strut the ship balanced just about perfectly without the need for additional nose weight. The new ship came out 1/2 ounce lighter on the Nats scales compared to last year's ship. The new one weighs 62 ounces and last year's ship is 62.5 ounces. Note that the new ship is stretched all over and hence is bigger. The new ship has one inch per panel more wing span, 1/2 inch per panel more tail span, a one inch longer nose and 1/2 in longer tail moment. So, compared to last year's ship, this one has a lower wing loading. Can't say that I really notice the difference in flight performance however...
I do know this: Everyone (Judges, co-competitors and spectators) told me that this new version presents very well in the air. I've always believed that having a signature look to my models was important. I like my models to be unique and have a look that is different than everyone else's models. It is one of the many intangibles of our event; setting yourself apart from the crowd is often likely to gain attention. Sometimes that's good and sometimes that's bad. I think in this case - this time - it was a positive.
Am I going to continue trimming and adjusting on the new ship? Certainly. In fact, I never stop trying to find more performance in all my models. Just recently I made great gains in flight trim on my Genesis Extreme. That ship was built in 2,000!
I used a Cobra 28/26-10 this year. It has a huge bearing in it (not that I was having any bearing problems with the E-Flite Power 25 that I had used in the past), and it is extremely quiet, even compared to the previously acknowledged quiet electric setups. I like the lack of noise most of all in electric. I think it makes the performance seem even smoother.
I'm going to try a lower Kv motor soon and that will allow me to try the 5S batteries that many are touting. Leave no stone unturned... I'll also be trying a variety of three-blade props (both pusher and tractor). I'll try lines that are a foot and a half shorter as well. I like the solids that I've been using for many years, but will give cables a try too.
I do believe that there is more performance to be had from this ship, but I am well pleased with how it flew at the Nats with only a handful of patterns on it. I left for the Nats with only six full patterns on the ship! It now has somewhere around 35 flights on it. Third was not bad for such a new ship, but I really should have put well over 100 flights on it before the Nats. It was not to be...
I now have two really great flying Crossfire Extremes in my stable and can start to experiment with other configurations. Certainly my Second Wind twin is at the top of that list and I'm getting back to work on that one now so that it will be ready to fly in the spring of 2014. Hopefully I can get those 100 or so practice flights on that one before competing with it.
I have several new and very radical ideas that I want to try. Electric power certainly allows for experimentation with multiple motors and unique motor placements. There are a number of other things that electric power allows, and Dean Pappas and I are examining some stuff that promises to bear a lot of fruit in the future.
I had given a lot of thought o retiring from competition this year, but I've changed my mind and have decided to rededicate myself to development and competition flying for as long as the Good Lord allows.
It just keeps getting better... Bob Hunt
Topic: Crossfire Extreme XLTC (Read 20930 times)