Originally posted by Alpha.MotionRC
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Hi HellHath, good to see you received yours. Our Stateside containers are anticipated to arrive later this week, and before they do I want to publish some insider information so it's fresh for all of you as you take delivery of your Skyhawks. Consider the following as Essential Tips from the Design Team. We've put years and over 500 flights by now on these aircraft, so, please take them to heart.
Throws, Neutral Positions, and CENTER OF GRAVITY. I've summarized the manual's information into the image, below. Note that early versions of the printed instruction manual may be unclear as to the forward location from which we measure the CG. The inset picture shown here is correct, as are these real life photos that also show the relative neutral positions for your maiden flight.
Aileron neutral point. The upper surface of the aileron is flush with the upper surface of the wing. Note that this causes the aileron's TE at the outer tip to angle upwards. This is reflex, and this is normal.
Elevator neutral point. Flush, as shown. Use the mold lines on the TE as visual reference. Sometimes I end up trimming ~1mm up elevator.
Battery placement. Like many of our other 80mm EDFs, we designed this aircraft with the Admiral 6s 4000mAh and 5000mAh in mind. Recognizing that some of you hotrods may see the A-4's potential for an 8s 80mm setup so we designed the layout so the stock PNP 6s batteries (lightest recommended) would be near the front of the bay, not the far back of the bay. I recommend maidening with the heavier battery, if you're concerned about overcontrolling this agile aircraft. Note the battery position. We measure the CG without the ordnance attached. With or without the hump doesn't matter. Whether the gear up or down and whether the model is balanced upright or inverted does not significantly alter the CG point when balanced on fingertips (less than 5mm). When you've flown the model as much as we have, it's usually just "shove forward and fly" for anything between 4000-5000. But obviously for the first few flights, we recommend checking your model. Using too much epoxy to secure the tail, for example, can throw off the balance, so always check your own model before ascribing to my personal generalities.
Landing:
As shown in the flight videos posted thus far by Ryan, Tony, and others, the A-4 is a nimble aircraft that above almost anything else is designed to land as easily as possible for an aircraft of this layout. It's not a rocketship, nor did we design it to be. Early prototypes traded away too much slow speed stability for straight line speed. The Mirage and MiG-21 taught us that the majority of our customers appreciate a model that lands well, not just one that flies quickly in a straight line. I strongly, strongly suggest every A-4 pilot-to-be studies Ryan's video that shows, up close, just how slowly and stably the Freewing A-4 can land. DO NOT land hot. DO NOT over-control the elevator. Recall three years ago when I talked openly about each new Freewing aircraft being a progression in terms of handling and skill. The A-4 will reward pilots that fly the aircraft down slowly with minimum elevator input. If you find yourself pulling too much back pressure in your descent, you're going too fast. Recommend going around for another shot. The one thing that is tricky about landing the A-4 is that, as a delta [essentially], it can fly slower/steeper than it wants to land. The MiG-21 is a good example of an aircraft that can fly to a near standstill at 40 degrees nose high. The A-4 will do the same. Obviously both models can't land at that attitude, so the key to a greasy A-4 landing is the same as the MiG-21 --managing your speed in a near flat descent with nose ~5 degrees up. I don't land with flaps, but that's just me. I prefer to bleed speed off on my base to final then manage descent with small blips of throttle while holding the very slightest amount of back pressure. The smallest of flares just as the mains touch will grease a landing every time assuming your speed is correct.
Faster or steeper approaches, or over-controlling the elevator, will cause problems. A good rule of thumb is, if the aircraft is ever below your head's height and the nose is greater than 30 degrees up, POWER TO FULL, STAY LEVEL, AND GO AROUND.
Flying:
Flying the Freewing 80mm A-4 Skyhawk is a bit of a non-event, by design. I've flown a bevy of A-4s.... GWS, LX, Jepe, YA, BVM, Tam, Skymaster. Our intent was to bring, as always, a good balance between price, performance, scale fidelity, and accessibility for as wide a range of EDF pilots out there. In the context of other 80mm EDF Scale Jets (the fantasy Avanti doesn't count!), I'm happy with the final result. For anyone who has flown one or two of our 80mm or 90mm EDFs and flies them comfortably, the Freewing 80mm A-4 Skyhawk should be well within your comfort zone. Just keep an eye on it. Let us know what you think! I
Throws, Neutral Positions, and CENTER OF GRAVITY. I've summarized the manual's information into the image, below. Note that early versions of the printed instruction manual may be unclear as to the forward location from which we measure the CG. The inset picture shown here is correct, as are these real life photos that also show the relative neutral positions for your maiden flight.
Aileron neutral point. The upper surface of the aileron is flush with the upper surface of the wing. Note that this causes the aileron's TE at the outer tip to angle upwards. This is reflex, and this is normal.
Elevator neutral point. Flush, as shown. Use the mold lines on the TE as visual reference. Sometimes I end up trimming ~1mm up elevator.
Battery placement. Like many of our other 80mm EDFs, we designed this aircraft with the Admiral 6s 4000mAh and 5000mAh in mind. Recognizing that some of you hotrods may see the A-4's potential for an 8s 80mm setup so we designed the layout so the stock PNP 6s batteries (lightest recommended) would be near the front of the bay, not the far back of the bay. I recommend maidening with the heavier battery, if you're concerned about overcontrolling this agile aircraft. Note the battery position. We measure the CG without the ordnance attached. With or without the hump doesn't matter. Whether the gear up or down and whether the model is balanced upright or inverted does not significantly alter the CG point when balanced on fingertips (less than 5mm). When you've flown the model as much as we have, it's usually just "shove forward and fly" for anything between 4000-5000. But obviously for the first few flights, we recommend checking your model. Using too much epoxy to secure the tail, for example, can throw off the balance, so always check your own model before ascribing to my personal generalities.
Landing:
As shown in the flight videos posted thus far by Ryan, Tony, and others, the A-4 is a nimble aircraft that above almost anything else is designed to land as easily as possible for an aircraft of this layout. It's not a rocketship, nor did we design it to be. Early prototypes traded away too much slow speed stability for straight line speed. The Mirage and MiG-21 taught us that the majority of our customers appreciate a model that lands well, not just one that flies quickly in a straight line. I strongly, strongly suggest every A-4 pilot-to-be studies Ryan's video that shows, up close, just how slowly and stably the Freewing A-4 can land. DO NOT land hot. DO NOT over-control the elevator. Recall three years ago when I talked openly about each new Freewing aircraft being a progression in terms of handling and skill. The A-4 will reward pilots that fly the aircraft down slowly with minimum elevator input. If you find yourself pulling too much back pressure in your descent, you're going too fast. Recommend going around for another shot. The one thing that is tricky about landing the A-4 is that, as a delta [essentially], it can fly slower/steeper than it wants to land. The MiG-21 is a good example of an aircraft that can fly to a near standstill at 40 degrees nose high. The A-4 will do the same. Obviously both models can't land at that attitude, so the key to a greasy A-4 landing is the same as the MiG-21 --managing your speed in a near flat descent with nose ~5 degrees up. I don't land with flaps, but that's just me. I prefer to bleed speed off on my base to final then manage descent with small blips of throttle while holding the very slightest amount of back pressure. The smallest of flares just as the mains touch will grease a landing every time assuming your speed is correct.
Faster or steeper approaches, or over-controlling the elevator, will cause problems. A good rule of thumb is, if the aircraft is ever below your head's height and the nose is greater than 30 degrees up, POWER TO FULL, STAY LEVEL, AND GO AROUND.
Flying:
Flying the Freewing 80mm A-4 Skyhawk is a bit of a non-event, by design. I've flown a bevy of A-4s.... GWS, LX, Jepe, YA, BVM, Tam, Skymaster. Our intent was to bring, as always, a good balance between price, performance, scale fidelity, and accessibility for as wide a range of EDF pilots out there. In the context of other 80mm EDF Scale Jets (the fantasy Avanti doesn't count!), I'm happy with the final result. For anyone who has flown one or two of our 80mm or 90mm EDFs and flies them comfortably, the Freewing 80mm A-4 Skyhawk should be well within your comfort zone. Just keep an eye on it. Let us know what you think! I
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