T-Hawk RC Partner Trainer

 

 

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The Sport Aviator’s aircraft photos that start each review, we call them “Lead Photos”, are always of the airplane in flight. Airborne pictures are just more interesting than box top photos. Flying pictures are better unless there is something very special about the box or its contents. The T-Hawk’s box is nothing special, just a plain brown wrapper so to speak. However, the box’s contents are incredible. (But we also included a flying Lead Photo [number 2] just for tradition’s sake.)

The T-Hawk meets all the aircraft requirements of the Academy of Model Aeronautics’ (AMA) Park Pilot Program. The aircraft weighs less than 2 pounds (the Program’s upper weight limit) and has a level top speed under 60 mph (the Program’s upper speed limit). For complete Park Pilot aircraft details, follow this link.

The AMA Park Pilot Program offers non-AMA members the opportunity to become AMA members at a much reduced cost. Park Pilot membership includes a great magazine “Park Pilot”, $500,000 personal liability insurance, $2.5 million liability insurance for the flying field owner (see insurance details) and membership in the world’s largest sport aviation association – the AMA. For complete information and details about Park Pilot membership, just click here.

Ready To Fly Fun (http://www.masportaviator.com/redirect.asp?website=ArticleLink_ReadytoFlyFun_THawk) has been a small aircraft specialist since 2001. They specialize in offering high-quality aircraft at affordable prices. All of their aircraft can be flown in school yards, parks and even at RC flying fields. But now, this company has put together a real Trainer Package designed to help every new pilot succeed. This is the most complete trainer setup we have seen to date.

  

Photo 1         Photo 2

The T-Hawk arrives in two separate boxes. One is a long triangular tube that contains both wings; there really are two wings. Attached to the wings are both stabilizers and both vertical fins. Yes, there are two of each of those as well. The T-Hawk Trainer Package contains an extra stabilizer/vertical fin assembly in case one is damaged during flight training. While other companies make replacement parts available by ordering, the T-Hawk supplies them with the airplane to avoid lost flying time if an unplanned aircraft/ground interface does occur.

The larger wing is the trainer wing. This 58-inch span wing is designed for slow flight, gentle turns and easy flight régimes. It is made from press-molded PVC laminated foam that is fabricated by splicing 3 sections of the standard high performance wing and then reinforced with wood and carbon fiber rods. This makes for a strong but light structure

The shorter, 40-inch wing provides higher airspeeds, more aerobatic performance and advanced training with a somewhat “hotter” aircraft. It is made from press-molded PVC laminated foam and stiffened with a wood spar.

The contents of the second box proved to be very different. Note in photo 2 that there are two (2) transmitters. Both are full-function, 72-MHz transmitters featuring servo reversing, V-tail and elevon mixing plus Travel Adjust on the elevator and aileron/rudder channels. Both transmitters have crystals; ours were on Channels 27 and 35. The Package also includes a 6-foot trainer cord to connect both transmitters together.

That is the idea behind two transmitters. The T-Hawk includes a complete “Buddy Box” system at no extra charge. Dual controls are a great way to learn to fly. The student pilot has more confidence and can concentrate more on flying and less on making a disastrous mistake. The instructor feels more comfortable allowing the student to get further into potentially bad flight areas before regaining control. Buddy Boxes are especially valuable during landing training.

In addition to the two transmitters, extra tail feathers and two wings, the T-Hawk Trainer Package also contains two flight batteries. These 8.4-volt Nickel Metal Hydride (Ni-MH) 1000 mAh batteries provide more flight time than we expected. Three propellers are included just in case. Although it is hard to imagine a situation that would break one of these tough, rear-mounted propellers, two extra are provided.

There are two landing gears in the Package. The heavier, more rugged gear is for grass takeoffs and landings while the other, much lighter one, is used for hand launches or paved surface operations. The battery charger includes an adaptor for 120 VAC operation as well as a 12-volt power cord that plugs into the standard car socket. Plenty of extra rubber bands and the instruction book complete the Package.

Assembly

 

Photo 3

The T-Hawk is a true Ready-To-Fly (RTF) aircraft that requires less work than the usual RTF. The assembled fuselage contains the 6-Channel receiver, two servos, the 15 amp micro-speed controller and the “improved” 480 motor. While I am not sure what the “Improved” means, this powerplant does seem to have more power than the usual 480 motor. Photo 3, a manufacturer’s cut-away picture, shows the position of each fuselage component.

The manufacturer’s cutout picture was used because we were not about to destroy the airplane just for a photo-op. Besides, the fuselage is made from very thick, very strong polyethylene and would be exceedingly hard for me to cut. It is also nearly impossible for a student to destroy.

Photo 3 also shows one of the T-Hawk’s best safety features. There really is an on/off switch. Most aircraft in this class do not have this feature. Without a switch, once the battery is connected, the motor can always start accidentally. This is not possible with the switch installed. The T-Hawk also has a delayed start safety feature. Before the motor will operate, the throttle stick must be fully advanced for about 5 seconds, and then brought back to off. Then the motor will obey the throttle inputs.

   

Photo 4         Photo 5

Photo 4 shows the entire fuselage assembly and the parts used to complete it. Not much work needed here. The first step is to install the propeller. Support the motor from the rear as shown in photo 5. Then press the propeller onto the shaft until it bottoms.

   

Photo 6         Photo 7

Remove the end cap from the carbon fiber, strong and light, fuselage boom. Note that there are two threaded rods on the bottom of the vertical fin. Thumb nuts are attached as shown.

   

Photo 8         Photo 9

Slip the twin threaded rods on the vertical fin’s bottom through the horizontal stabilizer as shown in photo 8. Make sure the elevator control horn is on the top side. Install the assembly onto the fuselage boom as shown in photo 8. Look into the boom through the end as in photo 9. Make sure that the antenna wire remains clear of the two rods.

   

Photo 10         Photo 11

Once the tail assembly is fully installed, slide the tail wheel onto the rod ends (photo 10). Secure the whole thing by hand tightening the two nuts as shown. There is no need to over tighten these nuts, hand tighten only. Once the rear assembly is complete, re-install the tail boom end cap. Allow the antenna wire to extend out the rear.

The servos can be accessed by removing two pieces of electrical tape as shown in photo 11. The micro servos weigh less than 9 grams each. There is no real necessity in revealing the servos as the linkage is factory connected inside the fuselage. But the photo shows where they are just in case you need to check them.

   

Photo 12         Photo 13

There is a narrow slot just forward of the servos. This is for the light-duty landing gear. If you can use this gear, just insert it into the slot. It helps to press the two gear legs inwards during installation. The wire gear is excellent for paved runways or when using hand launches. The wheels are large enough that they will allow grass runway landings without causing the airplane to nose over. However, this landing gear prevents grass runway takeoffs on all but the very shortest of grass fields.

Ready To Fly Fun (RTFF) provides a stronger, larger landing gear for grass takeoffs. There are six small screws forward of the servo bays. These screws hold the servo tray in place. Remove only the front four screws. Leave the two rear screws in place to keep the servo tray in position. Install the larger landing gear as shown in photo 13. Do not over tighten the screws as they only screw into plastic. The larger 2.5-inch diameter, extra wide tires roll easily over most grass runways.

   

Photo 14         Photo 15

The finished landing gear assembly looks good and is extremely strong. However, the heavy-duty gear weighs just under 2 ounces so it does incur a weight penalty. But flight tests proved the T-Hawk didn’t much mind the extra weight. The forward canopy is held in place with a rubber band. Under it is the battery connector and storage area. Changing the flight battery was always easy and didn’t require any tools.

 

Photo 16

Complete the fuselage assembly by carefully, very carefully, inserting the two control wires into the middle hole of each control surface’s control horn (photo 16). The best way is to make sure the radio system is turned off to prevent servo damage. Use two hands, carefully press a bow into the control rod and use the other hand to slightly bend the control horn and insert the wire. Be careful not to break the control horn.

 

Photo 17

Although the wings appear flight ready in the pictures, the larger wing is not. Attached to a separate instruction sheet is a pre-made bracing wire used to insure that the large wing maintains the correct dihedral under all flight conditions. Use the two transmitter boxes to support the wing. Loop one end of the nylon cord over the wingtip so that the loop is about 2.5 inches along the wing cord (photo 18 below). Gently press down on the wing’s center, remember that “gently” part there, and loop the wire over the other wing tip.

   

Photo 18         Photo 19

Check again that the end loops are about 2.5 inches in diameter. The string should be between 3 and 4 inches above the wing as shown in photo 19. This brace keeps the wing in perfect alignment during steep turns and rolls. Yes, the T-Hawk can be rolled even with the large wing installed.

   

Photo 20         Photo 21

Once the brace wire is in the correct position, secure it there with a small piece of transparent tape. Speaking of tape, the T-Hawk wing is further braced on both sides by strong “spars” made from packing tape. Neither wing showed the slightest tendency to flex under even extreme flight loads.

   

Photo 22         Photo 23

The T-Hawk is now complete. The entire assembly requires about 30 minutes, including the control surface check. This check is important. Install 8 alkaline batteries in the transmitter. Note the four servo reversing switches inside the battery compartment in photo 22.

The FlyRite RC transmitters will accept either standard AA alkaline NI-MH or Nickel Cadmium (Ni-Cd) batteries. The transmitter has a charging jack on the side if rechargeable batteries are used. No radio charger is provided but the polarity appears to be of the center positive, outside negative type. This equates to all charger types except JR. We used standard AA alkaline batteries in all flight tests.

The rear of the transmitter has the V-Tail, Elevon and Travel Adjustment features (photo 23). Make sure the mixing switch is in the “off” position. The travel adjustments were good as set at the factory.

Special Note: Unlike most buddy box systems, both FlyRite RC transmitters actively transmit except when the trainer switch is applied. That means that both frequencies are in use during the T-Hawk’s flight. Therefore, both frequency pins, or whatever frequency control system is in use, must be available before flying on the buddy system. As an alternative, remove the crystal from the student transmitter. The crystal is located on the lower right front side and is easily removed with two fingers. Store it in a safe place so the transmitter can be used in a later application. Without its crystal, the student transmitter can’t send out a signal.

Pre-Flight Setup

   

Photo 24        Photo 25

Both control surfaces must be centered. On this T-Hawk, the rudder was “left” and the elevator was “down” once the control rods were connected and the radio system switched on. Before making any adjustments, make sure that the transmitter’s right-side trim levers are in the middle, or neutral, position. Insure that the throttle stick and throttle trim lever are fully down in the off position. Turn on the transmitter and the receiver switch (install the flight battery first of course). Place the transmitter away from the work area to prevent accidentally moving the throttle control.

Use pliers to gently adjust the control surfaces to neutral by bending the triangle “loop” in the control rod either inwards or outwards (photo 24). In this instance, the loop had to be bent closer together (inwards) to move the rudder to the neutral position (photo 25). Do the same check on the elevator and correct if needed. Once these adjustments are made, turn off the receiver switch, make sure to disconnect the flight battery, and then turn off the transmitter.

30 minutes and the T-Hawk is ready for its grand entrance.

Flying the T-Hawk

There is not much to building the T-Hawk. No tools, except pliers for the final adjustments, are required. Everything is connected except the tail control rods and those hook up with fingers. There just is not much to do. So make sure you charge the flight batteries, that takes about 1 hour each, before starting construction. Why? Because you will be at the field in only a few minutes after first opening the box

   

Photo 26         Photo 27

The T-Hawk is really two aircraft in one. It might as well be two aircraft since at least two of everything else came in the Package! With the 58-inch wing and generous dihedral (actually polyhedral but whose counting?), the T-Hawk is a gentle, you won’t believe how gentle, basic trainer with good glider potential. The 40-inch wing transforms the T-Hawk into a mild aerobatic airplane with much higher airspeed potential.

   

Photo 28         Photo 29

Most pilots should consider limiting the large-wing T-Hawk to flights in 12 mph winds or less. The larger wing can handle higher wind speeds but the airplane might become too sensitive for new pilots. But the “bigger” T-Hawk is very comfortable flying in winds around 10 mph.

   

Photo 30         Photo 31

With a fully charged flight battery, the T-Hawk outdistanced our walking ability during the range check. With the antenna attached, we went out about 50 yards and then gave up because everything was still working. The controls moved in the correct directions and it was time to fly.

With the T-Hawk headed into the ~8 mph wind, the airplane went to full throttle and moved down the runway. Liftoff occurred after a 50 ft. ground roll off of a high-grass runway. Those large wheels really do work. There was some crosswind but the rudder proved effective in holding the wind-side wingtip down. The initial climb rate was good for this class aircraft. The airplane would hold a 20-degree climb angle under full power.

    

Photo 32         Photo 33

A steeper climb angle worked for about 30 feet but then required lowering the nose or stalling. Just to see what would happen, we held the high-angle climb. The airplane dropped its nose and banked left (photo 34). The aircraft righted itself almost before I could add the corrections. After trimming, some left rudder and about 5 clicks of down elevator, the T-Hawk flew straight and true.

   

Photo 34         Photo 35

Once airborne and comfortable at about 150 ft. altitude, we tried some turns. The T-Hawk responded and always stayed under control. But the airplane just didn’t seem happy somehow. Yes, it turned when instructed to do so, it cruised fine but it seemed as if numerous (but not constant) control inputs were required or the airplane would exhibit yaw variances (the tail moved around a lot).

I was a little concerned and thought that we would need some extra flight time to figure out what was going on. So I throttled back from 75% to about 30% power. Instantly, the airplane stabilized, the yaw variances disappeared and the T-Hawk looked very happy. The problem was mine. Without realizing it, I had been flying the big T-Hawk as if it were a standard, glow-powered aircraft. I should have known that the large wing with lots of polyhedral would wiggle the tail at high power settings.

   

Photo 36         Photo 37

At the reduced power settings, the big-winged T-Hawk was in its element. Cruising airspeed was around 10 mph. Turns were stable and well coordinated. The airplane remained level after the turn as long as the turn remained level. Like all under-cambered wing trainers, the T-Hawk would climb if it had gained airspeed in a diving turn.

   

Photo 38         Photo 39

The big wing T-Hawk would loop well from level flight. Loops were about 30 ft. in diameter and multiple loops were possible. Even a roll could be commanded but the T-Hawk asked that a positive 45-degree pitch angle be made first or the roll would start heading down too steeply. Adding down elevator while inverted slowed the roll too much so forget that part.

   

Photo 40         Photo 41

The T-Hawk was fun to fly and close fly-bys were simple to make happen. The airplane had already been airborne more than 10 minutes on the one charge when Sport Aviator’s cameraman, Frank Costello, suggested we tried flying the T-Hawk as if it were a powered glider. The airplane climbed to about 400 feet. Power was cut but the big-winged airplane just stayed high.

We had “caught a thermal” (warm air rising) and the T-Hawk did what all good gliders do in thermals; it climbed. With airspeed in the 5-6 mph range, this airplane stayed airborne for about another 15 minutes. Even though the motor was off, I began to think about how much longer the flight battery would last. The T-Hawk has a safety feature that cuts off the motor if the flight battery gets too low. This saves battery power to keep the radio system operating.

But if the motor is already off, how would the pilot know if the battery had reached a low level? With close to 30 minutes flight time on a new battery (Ni-MH batteries usually need 3 discharge/charge cycles to reach full capacity) it might be time to land this thing.

   

Photo 42         Photo 43

The T-Hawk didn’t want to come down but was forced to do so by holding the rudder hard over resulting in a gentle, descending spiral. The first landing attempt was too high as this airplane just won’t quit the air. There was plenty of motor power available for a second attempt. The big-wing T-Hawk approached the runway while flying around 5 mph. The landing only required about 20 feet of ground and was truly a non-event.

We later flew the big-wing version on the buddy box and the student pilot had no trouble enjoying the T-Hawk for an entire flight without instructor intervention. Flight time during this joint flight was 16 minutes. This means that the student pilot will have plenty of air time each flying session. Many small electric airplanes don’t provide sufficient flight time for efficient learning but the T-Hawk does not have this problem at all.

   

Photo 44         Photo 45

It was now time to put aside the trainer wheels and strap on the smaller aerobatic wing. We also removed the heavier landing gear to gain more performance. This meant that the T-Hawk had to be hand launched. But this was no problem as the airplane just left the launcher’s hand with little tendency to lose altitude.

   

Photo 46         Photo 47

Once airborne, the smaller winged version was noticeably faster. Heck, it was a lot faster. But even at high speeds, full power dives for example, the yaw axis remained steady without wiggling. Even though the airplane was faster and slightly more control sensitive, it would not be fair to say that it was any more difficult to fly than its big-winged alter ego.

Control response rates remained in the student range. Airspeeds were still less than 25 mph. Approaches were still power-off and very slow. In fact, the airplane had less “ballooning” tendency coming out of descending turns and that is always a good thing when learning to fly. Faster? Yes. Harder to Fly? Not really.

Performance-wise, the loops were larger and easier to control. Rolls however required a steeper climb angle first and could mutate into a split “S” if the pilot was not careful. A split S is a half roll followed by an inside loop. With the smaller wing, the T-Hawk performed well at low airspeeds but was no longer the true glider its larger version had been. But then, it is not supposed to be.

 

Photo 48

Landing the short-winged T-Hawk remained a non-event. The approached was less than 15 mph, probably closer to 10 mph. Touchdown required maybe 5 feet more than the previous landing. If you like faster flight, use the short wing. If you are training, like gliding around for maybe an hour, of just want something slow to sit and fly for a while, use the larger wing.

However, the shorter wing does have one huge advantage. The T-Hawk will fly well in winds up to 20 mph using it. At the recent Boy Scout Camporee that was held at the Academy of Model Aeronautics’ (AMA) Muncie, IN facility, 1,200 acres located about 200 miles from the nearest obstructing tree, Michael Ramsey (Model Aviation’s Associate Aeromodeling Editor) and I each flew a short wing T-Hawk in winds well over 25 mph and gusting to over 30. Both airplanes remained controllable and we even did some formation flying. How is that for small aircraft wind performance?

With either wing, you will find it extremely difficult to take advantage of the T-Hawk’s other safety feature. With the airplane secured on ground and the motor off, try turning off the transmitter but leaving the airplane’s radio system turned on. The T-Hawk immediately starts an incessant beeping. That obnoxious sound is the aircraft locater. If your T-Hawk ever gets lost in the rough, turn off the transmitter and follow the beeping sound to your airplane. A downed aircraft locater is another special feature not usually found in any aircraft, regardless of its size or complexity.

The T-Hawk is available as the complete trainer package described here. The price for everything, including the second transmitter is $280. That is a good deal for the RTF airplane alone. Add in all the other items and it is a great deal. The airplane is also available without a receiver, the servos are in there however, but no transmitters. There is also a 27 MHz version ($230) but this may not always be a good idea in our sometimes CB-crazy country with all the 500 watt skip idiots out there.

Check out the Ready To Fly Fun website, http://www.masportaviator.com/redirect.asp?website=ArticleLink_ReadytoFlyFun_THawk for complete details.

As with any RC aircraft, the student pilot should have an instructor when learning to fly with the T-Hawk. The T-Hawk just makes it so easy by putting everything into one package that learning to fly is a snap after you locate an instructor. Even for experienced pilots who want a break from their 44% scale aerobatic giants or their high-performance Precision Pattern masterpieces, the T-Hawk provides excellent flights and lots of fun.

Q

Specifications Wings: 58 inch training wing & 40 inch sport wing Wing Areas: 315sq. in. & 217sq. in. Length: 32″ Weights: 22oz & 19.5oz (w/o land gear): 24 oz. and 21 oz. with HD gear: 22.5 oz. and 20 oz. with light duty gear. Motor: 480 direct drive Std Battery: 8.4V 1000mAh NiMH Flight Time:  18-20 minutes under power. Unlimited flight time when gliding.Great Appearance; Flexible

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