80mm EDF vs. 90mm EDF for freewing A6 intruder

[Skip.Foley]

The A6 Intruder model comes with a 12 blade 80mm ducted fan. Is it possible to use a 90mm ducted fan or will this weaken the foam air frame. My landing abilities are questionable, so I don't want to weaken anything. I've read a couple of reviews claiming this model is under powered, but none of them have described the power plant in use. So who knows if it is really short on the power side. I spent 3 years working the A6A avionics and know this plane was not designed for speed but to hall around 28 500 pounders (14000 lbs). I not looking for hi-speed but enough power to provide good maneuverability. Any thoughts or advice will be greatly appreciated.
Thanks in advance
Skip

[crxmanpat]

Skip,

I fly the A-6 on the stock 12-blade 80mm setup. And while this jet is by no means a barn burner, it is definitely NOT underpowered. It has very scale-like flight, but handles slow flight very well. The key is to keep it as light as possible (I use a max 4000mAh lipo), and keep it clean. I don't fly with the fuel tanks anymore, but I did get the bomb racks as it just looks too cool to fly without them. With this configuration, she flies just fine, can loop and roll, and lands almost at a walking pace with full flaps and minimal power.

The only thing to look out for is to make sure you keep the speed up in the turns. But that's the rule for almost every jet. Otherwise, she's an excellent jet!

[Konrad]

Something else to think about. The inlet on this jet is not the best, asking it to feed a larger fan might actually be counter productive.

Another possibility is to go with an inrunner 80mm fan upgrade. This probibly won't help with low speed thrust but might help with top end thrust/speed.
http://www.motionrc.com/freewing-80m...-motors-black/

I do like the upgrade in my Mirage 2000 and F5-Es with 1850KV motors. But as Pat said watch the weight. The larger power will need to be fed, and that usually means heavier batteries. I'm sorry to say but often power upgrades result in LESS performance as the variables often conspire against each other.

Remember that with jets almost all the review are guys wanting to go fast and faster (that is why they are into jets). So they almost all say "X" model needs more power.

Run her stock and clean. As you said you need some work with landings so work on that. I can tell you seeing a guy make a 200 mph pass and then bounce, tip, and over shoot the runway does not leave me with a good impression of his piloting skills. Now landing in a 90° cross-wind on the numbers now that takes pilot skill!

Going fast does NOT take skill, it just takes power!

All the best,
Konrad

[Alpha]

Hi there, Skip, first of all thank you for your military service to our nation! Our Freewing 80mm A-6 Intruder really is best in its stock PNP format. Trust me, I flew Freewing's first pre-production prototype and have logged hundreds of flights with it over the past 2.5 years. A 90mm EDF unit wouldn't fit, and its inlet and exhaust diameters are all wrong for a 90mm fan, anyway. It would be a challenge to make CG with the model as well, based on its available battery compartment size. I find the model flies very scale, with power for non-scale loops and inverted flight without any issues. If you're itching for nonstop vertical climbing power, that's the only time I'd recommend considering the Inrunner/100A upgrade.

[Skip.Foley]

Thank you very much! I will keep it stock. I've log 17 hours in the A6A as BN. I'm now ready to move to the pilot seat.

[bradl4648]

Hi guys

I have the A6 for the past 2 years and I fly this stock so I can in form people the truth about our jets and plane. On this jet here I find it to be a perfect balance of power to weight and to the way the original had flown. Like some one else had said this is not a super sonic jet at all quite like the A-10. It was built to be a precision light bomber low to the deck flier. For that roll speed does not mean to much go under the radar be able to see what kinda soup some one is eating and let the bomb drop in it and get out. This model does that to perfection and above like loops ,rolls,inverted even semi decent knife edge. I have flown this in clocked wind speed of 18 mph wind guest of 21 mph and did awesome (crosswind). Landing was fun but handled it OK and no I do not use a gyro in this not needed. I think another thing to mention is the way this can glide as well. with about 500 feet put the flaps to half flaps I can almost get 2 100 yard circles and land with out giving power to it. I also fly this off of grass with great success. The only real flaw I find with it is on crosswind take off if your not ready for it and you have the wing up just a little bit the wind will roll it over immediately so watch out for that one. All in all it is by far the best jet I have ever flown and I would recommend to a person jumping to their second jet by far.

[Skip.Foley]

Thanks I'm impressed. I'm not very skilled haven't flow anything for 20 years so I'm looking forward to getting back in the air.

[Konrad]

WOW! 20 years! An EDF might not be the best thing to use to get back your flying wings with. You might want to think about an aileron trainer maybe a heavy aileron ship. Whenever I come back from an extended time away I spend a bit of time with a low performance ship. I like simulators and all, but still there is something about flying the real thing that helps with the visual clues. Jets even more so as there is no prop wash to help with the low speed maneuverability. I'm sure you can fly the A6, but even I wouldn't use it as a warm up model after 20 years away from the sticks.

All the best,
Konrad

[Skip.Foley]

Thanks Konrad, you are right. Good point I will buy a trainer along with the A6 any recommendations?
Skip

[Konrad]

I don't know where your skill level was at the time you last wiggled the sticks. I assume you were at or past the point of an advanced aileron trainer. I'd think some of the 70 mm sport jets would be much like an aileron trainer and afford some experience with the lack of prop wash over the tails.

http://www.motionrc.com/dynam-meteor-70mm-edf-jet-pnp/

http://www.motionrc.com/freewing-reb...m-edf-jet-pnp/

I often forget how long 20 years really is! I might even go back to a basic aileron trainer. Note the straight Hershey bar wings.
http://www.motionrc.com/great-planes...-wingspan-rxr/
http://www.motionrc.com/e-flite-puls...-wingspan-pnp/

[Alpha]

Here is a video I shot of Xplaneguy's A-6 Intruder. Everything is stock, with the stock recommended battery. This gives you a good idea of the jet's short takeoff, authoritative power, and most especially its stability in slow flight. In my opinion the aircraft doesn't need a 90mm fan shoehorned into it. The stock 80mm outrunner does great.

Great job, Tony! Always nice to see you at the airfield!

[Konrad]

Looks great! It looked like it lost heading at the top of the first loop (it also sounded like it, as we hear a grunt). I like the first slow fly by. We notice that the cameraman over leading and decided to wait a bit. He (we) didn't realize how slow she really was going until we see how long it took for the model to come back into the field of view.

This model is always on my list for my next jet. She just keeps loosing out to whatever I purchase.

i think the last line said it best: A pattern Jet.

All the best,
Konrad

[OV10]

Alpha,
Thanx for the vid, it certainly made my day on a dreary 5 degree F upstate NY day. Totally concur with you that the Intruder is more than sufficiently powered with the 80mm and I really love mine especially after I changed the livery to represent the squadron I was with(VA-35) in the early 70's.

http://www.hobbysquawk.com/filedata/fetch?id=28904

My only angst with EDF's in general is the short flight time windows. Am hoping that the latest developments on Graphene batteries as a replacement to Lipo's is the way of the future. They've made some huge advances on that technology considering it was only discovered a little over 10 years ago.
Best regards,

[crxmanpat]

It's always a treat when I get to fly with Tony. Last time was at Chino Valley, AZ back in October and we got to do some formation flying. I take this bird to the field with me every time and she gets at least 2 flights per trip. The guys at the field still love it, and so do I!

[Alpha]

Didn't someone capture photos of your Two Ship, crxmanpat? I wasn't there but I heard about those tight formations you and Tony fly with your A-6s.

[crxmanpat]

Yes, Ben got a few:

[xplaneguy]

Sure enjoyed those flights Pat! :)

Great job on the video Alpha, always a pleasure flyin and hangin with you. That A6000 is a sweet camera, Evelyn's trying to talk me into buying one. See what happens when you put a great camera in the hands of a young, professional photographer......I hear, "Spank that credit card Dad!" :)

[Alpha]

Evelyn's footage of our mass formation came out great, she's a natural videographer. Working on editing those throughout this week's evenings.

[xplaneguy]

I agree! Evelyn's experience as a pilot has really helped her capture aircraft in flight.

I've posted a number of videos on our YouTube channel that she shot. The Cox .020 & .049 flights are not easy models to film in flight:

https://www.youtube.com/channel/UCL4hahmxvsHrWFrT0O0f8TQ

[Kenny d]

Made a few crappy videos myself. Flew at Grumman.