Four Piper YO-59 aircraft were successfully evaluated and by 1942 were redesignated to L-4 (L for Liaison). With improvements to what was basically a Piper Cub airframe, components were added and modified to make it battlefield ready. With its rugged construction, extra cabin bracing and large windows, many successful rolls in reconnaissance and observation were undertaken by the Grasshopper L-4 for decades in war and peacetime with production ending in 1981.SPECIFICATIONS
- Wingspan: 2750mm (106.6 in)
- Fuselage: 1720mm (67.7 in)
- Weight: 6.9kg (my scales 7.8kg)
- Radio: 6 channels, 8 servos
- Engine: 20-30cc
- Hitec Aurora 9X radio
- Optima 9 channel receiver
- Miracle Twin switch
- Hitec 645MG servos: ailerons, rudder and elevator
- Hitec 485HB servo: flap and throttle
- Hitec HS 55 servo: ignition kill
- Extra long servo horns
- H/D extension leads: 4 x 300mm, 2 x 150mm, 2 x 500mm, Y lead
- 2 x 6 volt Awesome 2200mAh Ni-mh RX, ignition batteries
- 1000mm spiral cable wrap
- 500mm Velcro
- OS GT 33cc petrol engine
- Menz 18″ x 8″ propeller
- Phoenix Models pilot
- 91 octane, 32:1 Petrol Max oil fuel mix
As you can imagine with a 2700mm wing span, the thick carton protecting the Grasshopper L4 is so big it just about doubles as a work bench! Don’t like too much building, or should that be assembling? VQ have already done a huge amount of work to speed up the assembly time on this standoff scale kit. The fuselage, wings, horizontal and vertical stabiliser are built up from high quality ply and balsa, and covered in a PVC shrinkable covering. All windows are factory installed and access to the inside of the well detailed cockpit is from two doors on the right hand side which are fitted with magnet locks. The large red and yellow chequered fibreglass cowl is well finished and very rigid and plastic moulded engine cylinders heads need to be glued on.
Two large plywood seats are painted and used to hide the servos that fit in the cabins false floor. The control surfaces of the wings have factory installed hinges which have been glued in place, while the horizontal and vertical stabiliser hinges are hinged on one side for ease of installation of each surface. Wing struts are a spot on colour match with all mounting brackets installed and their scale looking support wires are bent and ready to install. The hardware pack is large and includes an alloy tube main wing span, assorted push rods and fuel tank if you are going down the IC path. The main landing gear is a fixed alloy type with glue on plastic covers and large scale type Piper Cub wheels which look good. Last of all in the box is a sticker sheet and an assembly manual.ON THE BENCH – THE WING
After reading through the assembly instructions, I preferred to change the assembly sequence and started by fitting the servos for the flaps and ailerons onto the wings hatch covers. To align the servo horn with the slot in the covers, 4mm plywood packers were added to the top of the servo rails and glued into place, and while gluing, I ran an extra bead of CA around the joints of the servo rails to hatch covers. 450mm servo extension leads were added to the aileron servos and the joins covered in heat shrink tube for safety. The factory installed pull strings make getting the servo leads to the end of the wing so much easier. The quality control horns are a straight forward fit on to the factory hinged control surfaces, and for peace of mind I added cut down dress making pins to each, doubly securing each hinge.
When reviewing a kit, I feel where possible all supplied hardware with it should be used as it’s part of the kit. While all push rods are adequate there is no lock nut for the back end of the metal clevis and I’m uneasy relying on the 2mm quick connector on the servo end of the push rod on an aircraft of this size. All the connectors were replaced with easy to install and use snap lock clips. The 2mm knurled nuts from the quick connectors will now be used as the lock nuts on the pushrods quick links. Four locating dowels hold the wings and align them to the fuselage. Thick CA was used to hold the dowels in place and the holes in the fuselage needed to be opened a tad to line them up. The non-structural wing struts use a 3mm screw into a Tee nut inside the fuselage, and on the wing self-tappers are used but with continuous use I felt the self-tappers will strip out over time, so I replaced them with 4mm wall cavity toggles screws that give much better durability. The wing strut supports are very clever and an easy fit up.FITTING THE FAN
To power the Grasshopper I’m using an OS GT33 petrol engine and after aligning it to the factory marked offset centre lines which are marked out on the front of the firewall, I drilled the holes for the engine mount screws, throttle and choke pushrods and then painted the firewall with a thinned down epoxy mixture to add more strength and extra fuel proofing. While the epoxy dried, I assembled the 3 line fuel tank. VQ have been very clever here as the fuel tank sits on a slide out tray that can be used as a battery tray if you are going to make the Grass Hopper electric powered. I mount a small sheet of glass paper to the tray to stop the fuel tank from sliding around and held the tank in place with the supplied cable ties. Mounting the engine is straight forward on the supplied 5mm screws. To add extra support to the engine mount screws I used large 5mm panel washer on both sides of the firewall and added lock nuts to the front side of the firewall and set the engine up with no thrust changes off the firewall. LANDING GEAR
I found that the thin plastic coverers used to sheath the alloy landing legs can be cut to fit inside each other giving great strength, and after l roughened up the glue contact areas, glue was applied to the legs and the covers. The wheels are nice with scale hub caps and the shock spring and wires fit with ease after drilling the legs. TAIL GROUP
After removing the very stiff covering from the slots for the vertical and horizontal stabilisers, a fuselage former blocked the installation of the horizontal stabiliser with nothing being mentioned of it in the instructions. With no alternative I cut it out with no ill effects to the strength of the rear section of the fuselage. After a test fit, the wings were installed and the entire tail group lined up spot on to the wings by both eye and measurement, a great result. After removing the covering from the glue contact areas the tail group and hinges were glued in place and again, cut down pins were added to all the hinges. Control horns are installed and connected to the factory installed push rods. RADIO GEAR
I repositioned the throttle servo higher up on the side of the fuselage for a straighter pushrod line up to the carburettor, just beside the choke push rod. My home made engine kill uses a mini servo and micro switch that is transmitter activated. I also installed a LED battery monitor on the floor for the ignition battery that is a snug fit when wrapped in foam and placed under the fuel tank. The rudder and two elevator servos drop straight in and the factory drilled pilot holes make starting the servo screws so much easier inside the cabin. A twin switch for the radio and ignition fits just inside the door and the receiver and battery fit under the false floor.
With the radio powered and all pushrod connected all surfaces were adjusted manually. Using the triple rates on my Hitec 9X, I set low rate as per the instructions and increased the remaining two rate steps by 15% for each step on all control surfaces. With virtually no wing dihedral, a full time 15% aileron to rudder mix will be a good starting point for nice scale type turns. The flaps were setup on a three position switch at 0 + 10 + 30 degrees and a full time down elevator mix of 5% and 8% respectively as a starting point. And last of all my receiver pack voltage warning was set to 5 volts on my transmitter.FINAL FIT-OFF
I had a 1/5 scale pilot that after some serious amputation surgery to his lower body would fit in the front seat and add to the great scale look of the plane. I also added painted cardboard over the servos and painted control horns, connectors and screws. Although stickers are supplied I think the Grasshopper looks so good I left the additional stickers off, but the choice to dress it up even more is yours. With everything installed a check of the centre of gravity (CG) would be difficult due to the size of the Grasshoppers so I drilled holes in the cabin wing mounts at the recommended C.G. point and threaded string through the holes and then fitted the wings onto the fuselage. I then lifted the plane off the ground and discovered the plane was tail heavy and 250g of weight was added to the nose to correct this. TO THE FLIGHT LINE
With the Grasshopper tipping the scales at just over 7.8kg, I had to get a MAAA heavy model inspection before I could fly it. The weather was clear skies and we had a stiff wind coming across strip. With the paperwork done, I was cleared to fly after the standard pre-flight checks were carried. The RX voltage was at 7.2 volts on the transmitter, and the range check being solid at 50 paces with the motor running. The OS GT33 was running well on 32 to 1 fuel spinning the 18” x 8” with ease. I taxied out and pointed the Grasshopper into wind and eased open the throttle and the OS responded. After a very scale-like take off run we were in the air on just 1/3rd throttle. What a beautiful take off.
In the air the Grasshopper was fantastic and the aileron to rudder mix felt spot on. After a few circuits I climbed up to about one hundred metres and cut the throttle to test the stall, even in the breeze it glided along so well with hands off, I was asked if I had the flaps down, but I didn’t. Back up to full throttle and it was time for some mild aerobatics. The OS was a good match for scale flying, loops tracked very well and straight. Next I did a roll, but it felt a little slow and I went to the mid-rate on the transmitter and it was so good I then strung 3 together, to a call of ‘that’s not scale’ as I did some inverted flight. Time to see what 10 degrees of flap can do; WOW the Grasshopper was moving so slow I was amazed, but the down elevator mixing was too high as I had to hold in a little up stick.
Time for the photos and I could come straight down the strip ever so slow, and I was able to put the plane wherever the photo guy wanted while having ample control response and confidence. Back up to high throttle and the speed was too fast for scale, but stall turns were just so much fun and graceful. With the high revving 18” X 8” prop I pointed the Grasshopper straight up and hung it off the prop to more calls of “that’s not scale!” I was so impressed I handed the transmitter to a fellow member and said “here have a go, it’s just like a big trainer – but better” and after only a few circuits he was hooked on the Grasshopper.
After what seemed like only few minutes of fun was acutely 20 minutes and I thought I must be getting low on fuel and should land, so reluctantly headed for home, dropping back to idle. The OS 33 ticked over on a low idle as the Grasshopper floated past on low flap for a very scale landing except that the side doors were now open and a lower wing strut bracket had broken, an easy fix. I guess the aero’s were a bit too much for what is ostensibly an observation platform!CONCLUSION
The VQ models standoff scale Grasshopper has had some minor niggly issues, but on the whole it’s a quality airframe. Don’t be fooled by its low price, it offers amazing value for money that will be hard to match. Best of all is the way it flies as it does everything so well, and is so much fun to fly that I can’t wait to fly it again and again and its size makes it very easy to orientate. It has some great detail added to give a scale look and painting a few minor things as I did, adds to the realistic look. It’s a keeper. Many thanks to Col Taylor Models for the opportunity to review the Grasshopper. Visit Col Taylor Models