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Old Jan 26, 2006, 11:03 AM
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JetMang's Avatar
San Diego, California, United States
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Ok, so I made a mistake. I weighed the airplane last night and the bare airplane weighs a 4.4 lbs

My appologies for any confusion...I've edited my other post.


Chris
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Last edited by JetMang; Jan 26, 2006 at 04:02 PM. Reason: wrong weight posted...again...
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Old Jan 26, 2006, 01:39 PM
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St. Mary, Maryland, United States
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WOW! That is quite a change

It may well still work, it is only about a 1/2 - 3/4 pound heavier than my Viper. But, since the margin has evaporated now I'd like to know an accurate weight on the retracts and struts - or just the struts, I assume standard Spring Air mechanisms do the lifting? What wheel size is needed? How much wing area?

And finally - how much will the color coats add? The primer only version might be the way to go if the production paint job adds too much weight...
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Old Jan 26, 2006, 04:01 PM
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Ok, so I just realized that my math was wrong...my scale gives output in ounces...but I divided by 12 as opposed to 16...DOH! So, the weight of the bare airframe is 4.4 lbs. (70 oz)

Oi, my head hurts now. So, that's it...I promise it won't change again! That college education sure did some good, huh?

@ Chris, to answer some of your questions, wing area is 552 sq in. I'm not sure the weight of the gear off hand, I would have to measure it. The mains retract through a mechanism we designed which uses two air cylinders which does not require retract units. Only the nose needs a retract unit.


Chris
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Old Jan 26, 2006, 07:11 PM
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All right, now I'm really confused .

4.4 pounds is EXCELLENT, I think you had corrected the figure to 5.5 pounds earlier (at least I SWEAR I saw it ) and that was the origin of my comment.

If it is 4.4 then the weight of the retracts doesn't matter too much - it all matters but starting from a smaller figure is easier to deal with. I'm always a little leary of LG designed for DF and turbine applications, I've seen some setups with solid rubber tires, brakes, struts and retracts that weigh nearly 2 pounds. Not yours but I'm sure you know what I mean...
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Old Jan 26, 2006, 09:44 PM
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upland CA
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Hi Chris, I checked with your dad to be sure I am on the list! would you guys post when you are ready to maiden it..I want to drive down.. I will SHOULD HAVE THE 104 READY!!
Scott
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Old Jan 26, 2006, 11:04 PM
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@ Chris, Yeah, I know. That was in Troy lbs though (12 oz to the lb). But since we're not talking about a precious metal...it's 4.4 lbs. I messed up on the math when I posted that.

@ Scott, I'm working on getting it ready to go. I'll keep everyone posted. Maiden will likely be down here at the Miramar club. Get that 104 done, would ya! ..and the Skyray.


Chris
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Old Jan 27, 2006, 09:21 PM
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Gaithersburg MD, United States
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Boy the A-7 looks sweet Chris!

I noticed there are two versions: a ducted fan version and a turbine version. I assume I should pre-order the DF version if I intend on converting it to EDF. Is that true, or does it not matter?

So what's next in the ARF line?

Thanks!

Paul
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Old Jan 27, 2006, 09:30 PM
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Quote:
Originally Posted by JetMang
Same post as in the "jets" forum.

Chris,

This design was originally built and flown for our Turbax 5" fan many years ago...and did not require an auxillary inlet. The FSA for the turbax is about 15 sq inches. I believe the inlet area is slightly less than that. The ducted fan version of the kit will have the full inlet duct to mate up to the 5" fan as well as the two piece ducted fan exhaust liner. The turbine version has the same inlet only cut back to open up for large sized fuel tanks and will not have the fibreglass exhaust liners as they are not required.

The aircraft in the pictures is essentially the first production prototype. Just requires paint and artwork which are being worked on. The models are being built using traditional build methods (ie. balsa sheeted foam cores which are then fibreglassed) which is helping to keep them light and affordable.



Chris
Sounds to me like the Turbine version is what you want if the fan will be 120mm. The inlet needs to be adapted anyway and the exhaust liner would be useless - use thin acetate instead.
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Old Feb 06, 2006, 01:25 PM
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Hi Guys,

Spent the weekend doing some painting. All base colors have been applied to the prototype. Just awaits markings and decals. I plan on doing that this week and hopefully start doing some radio installation.

This is in the Edwards paint which is the paint scheme we will be offering.


@ Paul, Sorry, no telling what the next ARF is just yet. It will be officially announced (and displayed ) at the Toledo trade show in April. Info will follow on our website after the show.


Chris
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Old Feb 06, 2006, 02:38 PM
Tear down the WALL!
ralf dvorak's Avatar
southern Germany
Joined Oct 1998
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uuuuh! What a beauty!!! 4,4lbs, well, sounds great!!! Should be nicely doable! If I only had more time and money and less other projects in the waiting.
Looking forward to see you guys' conversions!
cheers,
RD
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Old Mar 27, 2006, 11:47 AM
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Hi Guys,

I thought I would post a little progress on the prototype. We now have two prototypes getting ready to fly...the second (desert storm bird) is more representative of a production prototype and weighs 4.2 lbs, so have actually saved a couple ounces in the overall. The desert storm paint scheme is also one we are looking to offer in addition to the Edwards AFB paint. These are on their way to the Toledo trade show, so will be finished up and flown on their return.


Chris
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Old Mar 27, 2006, 12:04 PM
EDF all the way!
bruff's Avatar
Gilbert, Az
Joined Jun 1999
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Chris,
Looks Good! Will the paint versions be available in the first run of ARFs?
Bob
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Last edited by bruff; Mar 27, 2006 at 12:05 PM. Reason: spelling
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Old Mar 27, 2006, 12:29 PM
EDF Jet Jam 2015, May 28-31st
Robert Belluomini's Avatar
United States, KY, Crestview Hills
Joined Dec 2000
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Chris, Very nice work as usual! I will look forward to seeing this model at Toledo.
ETA on production models?
Bob
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Old Mar 27, 2006, 12:44 PM
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Thanks guys.

@BRuff, yes, the Edwards AFB version will be available in the first run. I'm not sure about the Desert Storm version it's quite possible it could be available also, all of the artwork is done.

@Agustapower, Please stop by and say hi. I'll be happy to give you a "tour" on the SLUF. ETA on the production models is looking more like May to early June. We've had to work out a couple production bugs, and are still finalizing some things for the aircraft.


Chris
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Old May 01, 2006, 01:48 PM
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Hi Guys,

Well, we test flew the Desert Storm A-7 on Saturday. What an easy flyer! Powered with the Wren 44 Gold, the airplane is a sweatheart! The airplane flies scale and really looks unique in the air. The first flight was kept short (about 4 minutes) with only 1-2 full throttle passes. The second flight was flown mostly at 50-60% throttle with the transmitter passed around (flew for 9 minutes). The airplane was a joy to fly. Really smooth and responsive on the controls and very stable. We were having some problems with the retracts so did not retract them for the flights and also left the gear doors off as well.

While recording video, I also was taking (or at least trying ) still shots, so have attached some pictures...not the greatest, but unfortunately the best I got. I will be posting some video as soon as I can.

FYI, we are currently setting up a DF version powered with an EDF. The power system should be ready for bench testing in the next couple weeks. The intention is to make the DF version interchangable for DF and EDF use. I will post details as they come available.


Chris
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