I'm not sure if Pike refers to the predatory fish or the the medieval battle pole. I will however be using this tool to skewer the competition by aggressively hunting for thermals. I like this plane. Samba Models makes them and explains all of the layup options on their web site.
The Pike Superior was the most popular choice of model at the 2004 F3J World championships, coming in first and third place. Conditions at the WC's were mixed, varying from windy with spread out thermals to late evening with very mild lift. Some pilots switched to a lighter plane for the mild conditions. There is little point in commenting on the performance characteristics of the model, by the time you are ready to buy one you will have developed personal preferences on how your contest tools should perform. C'mon, if this plane doesn't win contests for you, the problem isn't the performance of the sailplane. Needless to say, the plane launches very hard, is stiffer than necessary, works light lift well and can be landed accurately. I find it noticeably slower than F3B models and the Escape, faster than the American TD designs such as the Icon or Aegea. Also my preference is for cross tail fuselages due to the ease of tuning their flight character.
After seeing the contest and observing the best pilots in varying conditions, I decided to order a Pike, an Icon Lite and build a Supra. I should be ready for anything except a hurricane.
Rather than deal with the issues of international shipping, two of us ordered Pikes in August from Ron Turner at Spec'd Out Sailplanes. We chose our colours in January 2005 and the planes arrived in Calgary in March 2005. Ron provides great communication as your model is built and packs it well.
With a fight to get the most visibility, and not wanting identical planes, the two planes are basically reverse lime/orange.
Mine has orange tips and is dark blue on the bottom. This color scheme works well, the orange extremities are visible against clouds or blue sky when circling low and far away. My layup is the F3J light version with carbon center panel and carbon D-box tip panels. Surface finish is very good, and the paint is not quite opaque saving some weight. Some of the visible construction details are not the best, for instance the use of epoxy blobs to fill gaps everywhere no doubt increases the weight.
As a true ARF kit, the only work to be done is to install and wire the servos. Fuselage pushrods are installed and hooked up to the elevator and rudder. The hardware package provided is minimal. Other than the necessary joiners and bolts, only a 9 pin D plug is provided. The purchaser must provide wing wiring and aileron servo connectors, wing pushrods, clevises, ballast slugs and servo mounts. Finding metric clevises to fit the brass horns was a special order from the LHS. I pay $1300 for a plane and have to hunt down my own clevises?
At this level of expense and manufacturing, everything should be perfect. Or am I spoiled?
Elevator joiner rod fit. The front joiner is a 8mm diameter carbon tube and the rear incidence pin is 2mm steel. My elevator halves get stuck on the rear pin and are brutal to remove. Taking the rear pin and inserting it into each stab half is fine. Taking the pin and inserting it into the stab bellcrank is fine. There is obviously a spacing mismatch between the stab holes and the bellcrank holes. This problem is impossible to fix without introducing slop into the elevator so I'll have to live with it. The stabs will never come loose in flight, that's for sure.
Elevator servo horn- the elevator servo horn is very long to accommodate the even longer stab bellcrank. As the servo sweeps through the end of the big arc, the steel pushrod rubs against the pushrod support. This drags on the servo and flexes the rod. Overall the recommended setup works well.
Tip panel fit - the tip panel steel incidence pins did not fit the center panel holes and had to be drilled clean. Buy a metric drill bit set.
Wing connector mounting in center panel - A 9 pin D connector automatically hooks up the wing when the center panel is bolted onto the fuselage. Each mating half of the D connector is intended to be screwed down into molded recesses that ensure perfect alignment. Great. The fuse mold has some meat to hold the screws. This wing does not! You either have to figure out a way to glue supports into the inside of the wing skin for the screws, or do what I did. Just goop the connector to the skin and see if it will last.
Ballast system - Slugs for ballast are much harder to handle than one piece bars. I poured melted lead into 1/2" diameter brass tubing and cut the slugs to length. The servo tray access hole only allows the slugs to be 37 mm long and there are 8 slugs. The Escape has the best ballast system out there, changing the ballast is less than 10 seconds and two parts. To change from full ballast to half ballast in the Pike would require dumping out 8 slugs plus the retainer, and reloading 4 slugs plus 4 wood plugs, then reinsert the retainer. This takes about 3 minutes with all the pieces on the ground.
Wing mounting system - The center panel mounts with three 5mm socket head screws into metal sleeves. There is a lip on the bottom of the wing which mates to the fuselage platform so there's no chance of misalignment on bolt up.
Fuselage strength - A thick weave CF/Kevlar fuselage layup is bulletproof and radio proof. No pylon to magnify landing forces.
Servo pocket reinforcement - Samba has the foresight to add extra carbon where the servos are to be mounted.
Internal wing pushrods - Although harder to set up, completely hidden and drag free. Once the geometry is correct, the linkage is solid and slop free, though you can't use sloppy servos. Why would you cheap out on servos anyway?
Battery - the fuselage nose is large enough to hold a 5 cell AA pack in hump configuration. I chose the KR1100AA cells since they have plenty of capacity and take more fast charging abuse than the NiMH cells.
Tail servos - the fuselage tray is precut to take a micro servo, so JR 368s went straight in. Due to the long bellcrank on the elevator, the elevator servo needs an arm about 28mm long. JR does not supply arms this long but the Multiplex arms will fit JR servos fine.
Aileron servos - I had spare Volz Wingmaxx HP's so they are mounted in the frames. Good thing too, to get the pushrod geometry set up required at least three removals of the servo. A thin micro servo such as the JR 368 should barely fit.
Flaps - I prefer analog servos for flaps since these are the most likely control surface to get jammed. A jammed digital servo will lead to a meltdown of the plane due to either fire or battery drain. So the trusty Airtronics 141's go in except that they're slightly thick. I mounted them in basswood frames using the side tabs, and molded a new servo cover for the bottom of the wing.
Receiver - Lots of room for any receiver, even the full size Airtronics 8 channel will fit. Rather than try to save weight, the wing connector harness and wing servo leads are all 22 gage wire. The fuselage with big weave Carbon/Kevlar caused the first range issues I've ever had with a sailplane, the first in probably a hundred. I have always run the antenna inside the boom, no matter what, without any problems. On the 50 MHz channel 03 I could get >100 yards with the Tx antenna down and the Rx antenna at right angles to the fuse. Antenna inside the fuselage the range test was less than eight feet. Wow.
Next try was taped to the underside of the fuselage. Range 30 feet, not good enough. Final try was out the side of the fuse to the top of the fin, good for 80 yards. The external Rx antenna is a pain and causes drag, so switched back to a 72 MHz receiver. Inside the fuselage is 30 yards, probably could go with this. Taped to the outside of the fuselage is good to 60 yards. I ended up going back to the antenna straight out the fuselage, under the wing and to the tip of the fin. Moral is: range testing a new model is not to be skipped. No wonder the folks on 35 MHz have big problems. The Samba site shows many alternatives in anticipation of this issue. I don't like extending a tuned antenna, this changes the antenna impedance with unknown effects on receiver response.
Final assembly - JoJo Grini (a world class pilot) has provided full setup information for the Pike Superior on the Samba web site. Every manufacturer of competition sailplanes should do the same. No meaningless "safe" CG here, right on for proper performance out of the box.
Total time from box to first hand toss was about 14 hours in one week. Three were measuring and building the wiring harness. There are no instructions but there's no tricky step required. A recommended geometry for the flaps and ailerons linkages would be nice.
April 16&17, 2005 - A nice day for April in Calgary, light wind and 10 C. CG started 2mm in front of Jo Grini rearmost position. First launch is scary, straight up the line steep and hard. With the Ail/Rud coupling off, it takes a while to get used to the amount of rudder control necessary for coordinated turns. The rudder has plenty of control response, so it's not a matter of the vertical surface being too small. Effective dihedral on this plane is lower than the most recent designs even though I have the 4.5 degree joiner rods. The wind picks up to 20 kph and the plane travels downwind and back without problems. A few tests of the circling ability with and without camber to end the day. I think about the coordinated turns and develop a plan to test other configurations. The next day I settle on less differential and a small amount of rudder mix to compensate. When entering a turn the plane is coordinated, then top aileron is required to hold the circle. Since you are constantly moving the rudder anyway, the rudder mix is irrelevant. Less differential seems to help with proverse yaw when constantly circling and I need fewer rudder adjustments. Giving the amount of flailing away on the rudder stick, I don't think there is a coordinated turn setting which will get the plane flying acceptably in thermal turns. When traveling, the plane will turn efficiently up to 90 degrees without any rudder inputs. CG was moved back 1mm and no pullout in a dive.
April 23 2005 - Now that the plane is flying around to my satisfaction, it's time to wring it out. Not good, I am breaking new 170 lb. test braided line on every launch into a light headwind. Max tension launch testing will have to wait until the line is replaced. Here's a fun flight to 2315 feet.
Launch to 600 feet when the line breaks, hence no zoom. Search around for 2 minutes looking for a thermal and go up a little. Big wind shift and head for the main action, recentering twice at 700 seconds and 800 seconds. Start to lose the core at 2200 feet and about a mile downwind. Return to the field in a long shallow screaming dive that loses 1700 feet in two minutes. I like the visibility of this plane.
This flight on May 4,2005 is under better conditions:
Crosswind launch to 650 feet, not trying too hard. There's a good thermal downwind which takes a couple of minutes to chase. Leave the thermal at 7 minutes and the lift cycles through as the plane travels back upwind. After 25 minutes (1500 seconds), the Pike does some cross country cruising through the thermals at 1600 feet, traveling from a mile downwind to a mile upwind, then across the field. Sink moves over the field and I'm down to hand launch height at 54 minutes (3300 seconds). Drift with the zero sink for about 3 minutes and the core breaks loose in a turbulent stream upwards. Six minutes to climb out from 140 feet to 3074 feet, averaging 490 feet per minute up, then some speed runs across the sky. As you can see, conditions like this make hour long thermal flights meaningless when trying for LSF or CSS tasks.
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