|Wing Area:||155 sq”|
|AUW weight:||Advertised – 16 oz Actual - 15.4oz|
|Wing loading:||14.4 oz/sq. ft.|
|Servos:||2 – Hitec HS-55’s|
|Battery:||Poly-Quest 1500mA 3s LiPoly|
|ESC:||Jeti 22 AMP Spin|
|Available From:||Hobby Lobby|
|Cost:||ARF plane and fan $162.00|
Hobby Lobby and Alfa have teamed up again to give us a fantastic new EDF jet model. The Alfa A-4 Skyhawk is the fourth in a remarkable line of unrivaled scale jets. These all foam models are scale outlined and they all fly exceptionally well.
This plane has the same quality and detail work found in other Alfa model offerings. The paint is immaculate, and the panel lines and details are represented well. The A-4 Skyhawk is highly prefabricated, and it is ready to fly in just a couple of hours.
The review package shipped from Hobby Lobby and it arrived in great shape. It is well packaged, double boxed and the contents in the box were very well protected. All parts are individually protected with bubble wrap.
Included for this review:
These components are straight from the Hobby Lobby recommended list of equipment for this aircraft. Hobby Lobby does all the hard work for us making it easy to select the right equipment for success.
The Alfa A-4 Skyhawk will be ready with just a couple of hours’ work. Steps to add a functional rudder are not included, but on this model rudder is not really essential. It would be easy to add a functioning rudder if desired.
Done by the factory:
The builder needs to:
Per the instructions, I started construction with the fan system to get the rotor plug "glued" to the motor shaft. The included green loctite works well for this purpose. It was necessary to cut the shaft to the proper length before the plug was glued. Trust me, the green permanent loctite will hold that fan plug, but be sure you clean both the shaft and plug with acetone (nail polish remover) first.
Mount the motor to the fan as instructed. Follow the steps, allowing the plug to sit for 30 minutes and making sure that it runs up true which is important for balance and true running of the fan unit. It will then need to cure overnight.
It is easier to work with the fan unit with no other work done on the fuselage, so follow Alfa's recommended construction steps.
This Alfa will have wheels, but they only just poke out a bit for ground roll out.
The battery hatch is now secured by a couple of magnets - YEA!. That previous models have not used magnets has long been a complaint of mine on previous Alfa models. These magnets secure the hatch firmly yet allow easy access.
Installation of the tail feathers is simple. Use a sharp new hobby blade, and make a cut in the fin so that it can accept a small balsa joiner.
The elevator push rods were pre-installed, but I found the tube was not secured at the tail end or within the fuselage. I used a small amount of epoxy in three locations to secure the push rod tubes: at the rear exit ends (one for each elevator half), at the former location and at the end near the servos. Securing the tubes is required for proper elevator function.
The A-4 uses a single center aileron servo. Push rod tubes are installed but need to be glued at each end for proper function.
Adding the wheels to the wing is a simple matter. I am pleased that they are not really visible in flight, and they add a great option for hard surface take off. This really saves the Alfa A-4 from poor hand launches and is highly recommended.
I used the recommended 30 minute epoxy to attach the wing to the fuselage. You will need the extra time to ensure the wing is positioned properly. Gluing the wing to the fuselage adds significant structural strength to the fuselage.
While playing around with the wing, I did make one discovery: my plane rested on the aileron control horns when there was no battery in the nose. That had me a bit concerned as I didn’t want any chance of those getting knocked loose. I suspect the horns will not touch on takeoff rotation, but I added clear protectors to insure that when there is no battery pack, the model would rest on these protectors rather than the horns.
The Spektrum AR6100e receiver fit well right on top of the fan duct. I did use some foam double sided tape that will hopefully dampen duct vibration to the receiver minimized.
I chose to spot glue the hatch panel to the fuselage. I realize that I will have to "cut" to get access to radio equipment, but I like the structural strength the spot gluing added.
The Alfa A-4 includes the 3 blade Alfa fan. I used that along with the LittleScreamers JetScreamers motor and Jeti Spin 22 AMP ESC.
The motor with the 3 bladed Alfa fan (included) produced the following results:
The included Alfa 3 blade fan with the brushless motor certainly provides good sport power. Many like the additional thrust and speed that the Alfa 5 blade fan gives on 3s voltage.
This gives the A-4 186w/lb performance, allowing good sport power. The TP 1320 pack fits well also and saves a bit over an ounce. With that pack, the weight goes to 14.1oz AUW giving 205w/lb., so that makes an excellent light weight option.
Jeti Spin 22 AMP ESC
I currently own many Jeti ESCs, and I am a long time fan. The Spin line of ESCs avoids needing to use a separate BEC since they include a powerful integrated switch mode BEC. The switch mode BECs decrease the input voltage much more efficiently that linear BECs. This enables you to use the built in BEC for higher voltage 4s packs. Highly Recommended.
I used a single 3s 1500 mAh Poly-Quest pack to provide the electrons. I have many of the Poly-Quest 20c batteries and have never been disappointed with any of them.
Alfa has expertly painted the foam in an authentic light gray and white scheme. Although authentic, it really limits visibility until the colorful markings are applied. The paint finish on this plane is typical Alfa - impeccable. Not one single flaw was noted. The decal sheets are included and include options for three separate aircraft. Well done Alfa!
Alfa decals are very accurate, but they are made from thin material. I took time to carefully install the decals. After the decals dried overnight, I used a decal solvent to aid adhesion. The decal solvent actually melts the decals right to the model, allowing them to curve better which is important since this model has a few complex curved areas. After the decal solvent is set, I highly recommend spraying a clear coat to seal and protect the decals.
If you wish to step out and use your own finish, there are many military schemes for the A-4 so you can certainly go wild! Mine may get an Israel camouflage scheme or maybe the Blue Angels.
CG on this Delta wing is critical, so do not omit this step. Although Alfa includes balance marks on the bottom of the wing, many people balance this model inverted. I simply transferred the measurement to the wing top for reference. With the Jeti Spin ESC in the midsection of the fan duct, and with the 3s 1500 pack the plane was slightly nose heavy with the battery in the rear most part of the tray. If you use a heaver pack, you will need to relocate the ESC and perhaps the elevator servo to the rear of the aircraft.
I used my trusted Spektrum DX7 transmitter for this plane. Rates were set as recommended in the Alfa manual with ailerons and elevator at 12 mm and 15 mm respectively. No high rates were mentioned, so I set those rates to give 20% additional throw. No exponential rates were mentioned so I used 25% for elevator and 55% for ailerons. Do not use more aileron throw for initial flights. It rolls like a dart, and too much throw will be challenging on first flights.
I set the flight timer to count down from 6 minutes as that tends to be long enough! This gives an audible warning to land well before the 1500mAh battery is depleted.
I really do not get too apprehensive before test flying models, but I can assure you the adrenaline was flowing before the A-4 flight. I flew before the markings were added - a big mistake. It was simply too hard to see. Thankfully it flies very well, and I managed to keep the tire side down!
With the installed wheels on a hard surface, I rotated the A-4 after about 50 feet or so. Even with the negative incidence it rotates very well. The LittleScreamers motor lived up to its reputation and provided the necessary power. With the 3s and the 3 bladed fan mine will not lift off from the thick grass at my club field. Hand launching works fine, but you do need a nice level throw, and I do not recommend doing that yourself. The model does have a center plastic skid that works well for a hand launch grip.
Landings are easy as the Alfa A-4 with its delta wing slows dramatically in landings. The A-4 flares well and the elevator control rates were adequate. True of all most EDF models with no direct airflow over the elevator you will need to maintain speed and you will need all the available elevator throw on landings.
This A-4 is small and fast - it gets tiny very quickly. Keep it close, and turn often! As you can imagine, the A-4 rolls quickly. That may be an understatement - it rolls like a dart! It is also a top heavy model so it really likes inverted flight. It does great large loops and quick split S turns. It does need a fair bit of elevator in the turns, so do not be afraid of keeping on the sticks.
The plane stalls very predictably for a model with a light wing loading. When pushed to a full stall, you get a nose drop and roll. It slowed very significantly before stall, and it remained fully controllable right down to the last second. Stall recovery was quick with smooth throttle application. The horizontal stabilizer is fairly small, and the A-4 will depart controlled flight fairly abruptly. Common to delta wings, the A-4 rolls fast.
Overall flight is impressive, and speed with the 3 bladed fan is good. If you are looking for all out performance, the 5 bladed fan on 4s voltage or 3s voltage will give a nice boost.
Thanks to Dawnron1 for these excellent flying shots, no small task with this small fast jet:
Power from the brushless motor is excellent, but the 3 blade fan and 3s is certainly sport power. The 5 blade fan gives a nice boost in performance, but make sure your battery is up to the increased current draw. Many report excellent high speed flight with 4s setups as well. If you want speed you can certainly attain it with the Jeti Spin controller 4s.
The Alfa A-4 is for advanced pilots only. It flies fast, is designed to be hard to see so orientation is difficult, and it is a small aircraft that will get small quickly.
When I saw that Alfa was coming out with the A-4 I knew one was in my future. The "Scooter" is an all time favorite jet of mine. Alfa has accurately represented the model, and it is a stunning beauty.
Assembly is easy and straightforward. The A-4 flies very well with the included 3 blade power system on 3s voltage, but the JetScreamer motor is capable of far greater power including 4s and 5 blade fan configurations, so if you want more speed the motor will certainly oblige.
Alfa continues to impress me as they release more stunning models. The paint and finish on the A-4 is amazing, I could not find even one single flaw. The decals are accurate and represent the options for 3 different planes. This is very welcome on an ARF model as that gives you the ability to look different than the other guy. The Alfa quality and attention to detail is apparent throughout.
The Alfa A-4 Skyhawk looks amazing and proves itself to be an excellent performer in the air.
The Alfa A-4 Skyhawk makes a great addition to their already impressive EDF jet line. I highly recommend it! Check it out at your local hobby shop or buy direct at Hobby Lobby.Last edited by Angela H; Dec 28, 2007 at 02:03 PM..
Mike - Excellent write-up, well presented and formatted. The A-4 has always been one of my favorite jets (Blue Angels scheme is my favorite).
Ronnie - FANTASTIC pictures my friend!! Some of those photos look incredibly life like with the pilot figure in there.
You two make a great team!! Nice work gentleman.
Mike, I REALLY enjoyed your review of this fine Alfa EDF. You two (actually, you THREE, counting Doug! Wow, can he paint! Hey Doug, wanna branch out and help recruit those fine looking pilots for the West Coast review squadron!? <G>) sure do generate some first class reviews! I think you cover the details of assembling and flying this plane very well and you have a knack for clearly expressing yourself in your writing.
Two thumbs up on an excellent review of a must have plane! Well, I already have one...I just need to find the time to BUILD it! 5 blade and 4S for me!
Thanks Mike, Ronnie and Doug!
Thanks gang - it is a pleasure....... Ronnie makes the stuff look really good - as does Doug.
I have reviewed a number of Alfa planes - I can honestly say they are simply some of the best flying models you can own. They look fantastic and fly even better than they look.
The A-4 is a long time favorite of mine as is the A-7 - HINT ALFA team!
It will get a hop up soon! But I can say it flies very well on 3s and 3 blade. I know it will be a tad bit more fun with a bit more juice!
Here is my review model with a hyperion 4200kv motor and the stock three blade fan and a 3s 1200mah battery,
The blue five blade fan is currently installed and will be tested tomorrow on the same motor, the amp draw increased from 13 amps to 19 amps, should give a nice boost.
Here is some motor data from my Skyhawk;
Het Typhoon 240-15 with the 5 balde Impeller and 3s2100. Great plane and a great flyer. Gets very small very quickly. Only down side are the decals that do not hold long.
Your usual outstanding job, Mike!
I have been piddling with my Alfa Ta-183 Huck and I can confirm that decal solvent and a light coat of clear is the only way to go when using the Alfa water slide decals. Nice decals, very thin, but they will NOT live long without proper installation and protection.
This is probably one of the best review's I've Ever read
The only part that worries me is this:
It was necessary to cut the shaft to the proper length before the plug was glued. Trust me, the green permanent loctite will hold that fan plug, but be sure you clean both the shaft and plug with acetone (nail polish remover) first.
Just how much did you cut off?
Tom - WI
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