"Inspire" - Contra Powered Design - BJ Craft
 

I have received pictures and a short description of the new "Inspire" from BJ Craft. This model has been designed to be powered by the Brenner Sharpe Contra unit. Not only has the airframe been refined aerodynamically for the Contra, there is a new motor mount system specially created for the Contra.

I have been flying the Contra in all of my BJ Craft models. That includes the Nuance and two Episodes. While these models have worked well it did take some additions and changes to get the desired performance. BJ Craft has taken this experience along with their knowledge and testing with the Contra to develop this model.

A Contra Drive model needs to have the stability adjusted to counter the effects of the two large props. The tail volume in both yaw and pitch has been increased with a larger horizontal stab and increased fin area, most notably with a ventral fin on the bottom of the fuse. Since the Contra has excellent braking providing control over airspeed the drag of the model was reduced by using different airfoils. This allows for reduced power consumption yet retains the needed airspeed control. The force set-up has been adjusted with different thrust angles and incidences.

The supplied motor mount makes assembly of the Contra into the fuselage much easier. Attention has been paid to easy removal and installation making any required maintenance simple.

Here are a few pics of the "Inspire".http://www.rcuniverse.com/forum/atta...mentid=2014986http://www.rcuniverse.com/forum/atta...mentid=2014988http://www.rcuniverse.com/forum/atta...mentid=2014989http://www.rcuniverse.com/forum/atta...mentid=2014990http://www.rcuniverse.com/forum/atta...mentid=2014991http://www.rcuniverse.com/forum/atta...mentid=2014992http://www.rcuniverse.com/forum/atta...mentid=2014993

Here are pics of the motor mount.http://www.rcuniverse.com/forum/atta...mentid=2014994http://www.rcuniverse.com/forum/atta...mentid=2014995http://www.rcuniverse.com/forum/atta...mentid=2014996http://www.rcuniverse.com/forum/atta...mentid=2014997http://www.rcuniverse.com/forum/atta...mentid=2014998http://www.rcuniverse.com/forum/atta...mentid=2014994

Please note that the "Inspire" uses the flying stab that has worked so well in other BJ Craft models. I'm looking forward to receiving my model and will report on my observations. It all looks very good to me and I'm very confident it will be a great model!

Looks Great!
I think he really hit the nail on the head with the larger horizontal stab. Also, the enlarged vertical fin will really help. It looks well balanced overall. Looking forward to your flight reports.

Looks nice, I REALLY like the simpler color scheme.

Tom M

Herb Kurlan has the Inspire with the Contra (sent to him by BJ) and Herb flew it at the Nationals - only a few days practice with the plane.

Hey Guys the Inspire is on its way soon to F3AUnlimited.com
http://www.f3aunlimited.com/bjcinsite
We have it listed but not in stock yet. I have a good number on order and we have all of the support items needed for it too like the CRP Contra drives.
We have taken a few pre-orders for them but it's still a couple of months away from getting here.
Herb's was the prototype and brought over early so he could have it at the Nationals and we could show it off. He paid for it.
Thanks, Mike Mueller

We have today received our first demo Inspire and expect to have stock late November for sale across Europe
http://www.bondaero.co.uk/Inspire_CD..._10963645.aspx

Chris

http://www.f3aunlimited.com/bjcinsite
For sale shipping next week. We have a very limited amount left.
Don't hesitate if you. As the retail arm for Contra we are proud to have this offering.
Thanks, Mike Mueller
F3AUnlimited
800 591 2875

As Derek and Mike mentioned I have been flying the prototype Inspire since the Nat's and have been very happy with the performance. I received the plane after BJ put it together and flew it a few times. He then crated it up and sent it to me to take to the Nat's. I put it back together using all stock parts. Some of the stock parts I have since switched out like the Z bends in the pushrods. Trim wise the plane is very solid. I did feel that it required a little down with rudder. BJ recently suggested adding a 1/2 degree positive incidence to the wing and that took care of knife edge trim. I liked where he wanted the CG which is on the trailing edge of the wing tube. The only other change I made to the setup was taking some of the positive incidence out of the T Can which seemed to help Knife Edge. I used his motor mount which has no isolators but the motor is very quiet and the motor mount works very well. I would also suggest reinforcing the landing gear as I had a few incidences and had to do it involuntarily.
In between some much needed rain I have been practicing the new Master's sequence and the Inspire handles it better then I do.A few people have liked the design but didn't necessarily want to use a Contra, BJ said that adding 2.5 degrees of right thrust will work very well.
All in all a great design with a visible color scheme that incorporates the latest thinking on rudder authority, flying stab and the Contra makes it a good choice.

Herb

Thanks for your comments Herb!

I corresponded with Mike regarding the BJ Craft motor mount.
It is indeed an option because, apparently, some intend to build the plane without a Contra. Mike is charged for them, so must pass the costs on to his customers. Price is $75. Sounds like their availability is about a week behind the planes.

I had the same response from bondaero in the UK . Cost similar at £50.

Yes sorry about the mount confusion.
here is a picture of the Inspire built without the Contra. They added 2.5 degrees of right thrust. It takes a 82 mm spinner. If you cut back the nose to make it flush it could accommodate an 85mm spinner which we sell in the falcon brand for both 2 and 3 blades.
I'd like to see an Inspire with a nice 3 bladed prop. 3 Bladed props are really popular now much more outside of the North American market.
We have them available now from Mejzlik, PT Models. with new models coming very soon from SDC Composite and Falcon with 3 new sizes.
Three Inspire's left in stock. Thanks, Mike Muellerhttp://www.rcuniverse.com/forum/atta...mentid=2049521

Hallo,
I always thought that the Inspire is only for Contra Dives. I am current looking for a new F3A-Modell for the next season. I was shure to buy a Episode, because I want avoid the effort of a Contra unit. But now I am reading, that the Inspire also can be flown without a Contra unit.
I want to install a normal Hacker Q80 and at the moment it is the question for me which modell should I buy –Episode or Inspire?
So I think, that the larger horizontal stab und the enlarged vertical fin would also help when a normal electric motor is installed. Otherwise I red, that the Inspire has reduced aerodynamical drag, because the Contra provides good braking. Now I have the fear, that when a normal engine is installed the Inspire could be very fast on the vertical down-passages.
Mostly I fly the P programm but I also train some sequences oft the F programm. So my question to the experienced pilots which model would You recommend me. I am very interested in the Insipire, but I am not sure, which is the better model for normal engines –the Episode or the Inspire?

Regards
Gerhard

Hello Gerhard
I too thought it was supposed to be a one trick pony for the Brenner Contra unit. It's just recently that I was informed that the testing done on a 2 blade or 3 blade prop non Contra was working well.
We just received the planes on Wednesday here at F3AUnlimited. It seems logical to me that the changes made to the fuse are going to be effective for either setup. If BJ says it's good and he says they have tested it then he knows more than us.
The quality of the BJ Craft airplanes has been steadily improving over time. The differences are subtle but they are there.
We have just now started unpacking the new Passion Biplane from BJ/Akiba and it's really impressive. Very light and well done.
I'll start a new thread on it soon.
Thanks, Mike Mueller

Hallo Mike,
Best thanks for your information. So I think, the Inspire is a very interesting model for me.
I hope some guys will install a normal engine and will report soon about their experience.

Regards
Gerhard

Here in Colorado, a couple of us have become "Inspired"!
A couple of quick observations, many of which are apparent from previously published pictures:
-ARF has the usual BJ quality: No blemishes and not a single covering wrinkle.
-The wing is not the Episode DTFS. It has an extra taper near the tip, but not at the root.
-Looks like the same stab as used on the BiSide, but I don't have one for comparison.
-Very large rudder
-Smaller canalizer than the Episode
-I like the scheme. Red bottom should show up nicely. Other colors appear to be in wider stripes than on past schemes - this should reduce "visual blending".
-We will still have to grind the gear leg openings in the fuse in order to fit the landing gear in. Why, after all this time and so many models do we still have to do this?

Now, to get some quality workshop time.....
Dan

Sounds just perfect for me. Does the kit come with wing adjusters?

Kit has the standard BJ adjusters: position and lock in place.

I forgot to mention that there is a new canopy latch system that should be more secure than the Episode latch.

Hi,
A case of 'Spot the difference' ??.
Looks like different wings, fuz,, ,stab and fin/rudder group in these pic's.
What is shipped ; The wing from 1 and the rest from 2 ?

Brian

Very interesting. The second picture looks like an episode with the Inspire logo. All the pictures in the model shops are of the first picture you posted. I hope that is the model I am getting.
where did the second photo come from?

Hi mike, that photo you posted of the "Inspire " for normal motors (not contra) looks like an Episode with the Inspire logo. It's not the same as the Inspire CD that's picture for sale on your website! What gives?
http://www.rcuniverse.com/forum/atta...mentid=2052112
This is the first Inspire flown by Herb Kurlan.

Hi Paul,
I think that the fuz,, in that photo is a new fuz,,. It seems to be a lot deeper just in front of the fin.
However it does seem to have one of those double taper wings (the one with 3 tapers) on it as well a an Episode style rudder.

Brian

It also has the all moving tail. Does this mean there is an Insoire for the Contra drive and a different one for other set ups? Maybe somebody can clarify.

I received mine from Mike this week, Here are some pictures to show what is actually shipping for the Contra version

http://www.rcuniverse.com/forum/atta...mentid=2052185 http://www.rcuniverse.com/forum/atta...mentid=2052186http://www.rcuniverse.com/forum/atta...mentid=2052187http://www.rcuniverse.com/forum/atta...mentid=2052188http://www.rcuniverse.com/forum/atta...mentid=2052189http://www.rcuniverse.com/forum/atta...mentid=2052190

Bill

Hi Bill, looks really nice. That's the one I hope to get. Did you purchase the firewall/ motor mount assembly for the contra? It looks like it would be such an easy install with it.

Yes,

Dan Underkofler and I are both going to try it but the shipping on it is lagging and Mike was not expecting to be able to ship it for another week or two. Since this is my first Contra I am leaning on Dan for a lot of help. especially since we fly at the same field.

Brian point so noted. Your right. I took that pic on the right down. More news to come when I know more. It fooled me too.
Mike Mueller

Mike,
Ah ok !! - Thanks for the clarification.
It is a nice looking fuz,, .
Looks like the rear is a lot deeper and the cannaliser is mounted to the fuz,, (not the canopy).
We will watch this space so :)

Brian

We'll fly 'em next weekend then Bill?
Dan

I don't have details but I have been told that BJ Craft is working on a new model that can be built for glow. If you note in that picture there is also a chin cowl on that model. Not sure about the name. It's probably an early prototype in that pic.

Also, I have just received my Inspire and I will be doing an assembly thread as I put it together.

That's good news to hear. I hope it happens.

Hi tony, look forward to your build thread.

Hi Tony I look forward to the build thread.
I thought we ran out of stock yesterday but low and behold I found another Inspire at the warehouse. So one left till March or so when we will resupply.
It's very difficult to anticipate interest in a new design. This one has taken us by surprise.
We feel very privileged to be the North American rep for BJ Craft. BJ Park is a very nice person, fair and honest and the quality and value of his planes speak for themselves.
As his designs and company progress you can see an improvement in the quality. That is the mark of a good company. Not content to sit on their laurels striving to constantly improve.
It is their goal to produce the best flown by the best. Lofty but a great aspiration.
Take care and thanks for all the support my F3A friends have bestowed upon us.
Mike Mueller
F3AUnlimited.com

Mike, I couldn't agree more. I've been extremely happy with all the BJ Craft models I have had and currently have. I hated to mid-air my original Episode as it was really flying well. But it had 850 flights on it so it had a good life. Looking forward to putting those kind of flights on the Inspire. on the 23rd I get the first cataract surgery. If my procedure goes as well as I have seen my friends have I may even be able to really see these models now!

Thanks Tony good luck with the eye surgery. By all accounts I have from friends it's likely to be a big improvement.
I'm lucky I feel I still have very good eyesite. I thought I was having issues a few years ago but with me it turned out to be Polaroid sunglasses and prescription sunglasses with curvature. That screws with astigmatism's. Now that I have all that squared away I feel like a kid again.
Mike

I've had a chance to do a bit of work on my Inspire.

I wanted to note that the rudder servo is more conventionally mounted than on previous BJ models. There are open bays for both the rudder and elevator servos - this speeds up the build.

Mounting the landing gear has always been tedious. You have to put the gear leg in place, insert screws, then position the clamping plate underneath the gear leg by feel and hope to get the screws engaged. This gets harder on the Inspire because the access holes through the gear bulkheads are smaller (a good structural improvement IMO). I'll share what I've done on 2 planes now: Installed the blind nuts directly into the gear legs.
-make a light counterbore/spot-face for the outer blind nut. I did it by hand with a dremel cutter. Just go deep enough to get a flat spot on the leg underside.
- drill out the mounting holes from the bottom of the gear to the diameter of the blind nut. Don't drill all the way through, just deep enough for the blind nut.
- Mark and drill 3, 1/16" holes for the spikes of each blind nut. Tricky, but they don't have to be too precise. See picture 1
-Install blind nuts and pull into place with a screw.
- Add a couple of drops of thick CA or epoxy to lock in place. Picture 2 shows completed leg.
-Now just insert the leg and tighten the screws.
-Disclaimer: these operations on the gear leg for the outer blind nut weaken the leg in the highest stress area. I haven't had an issue with my Episode and 100s of flights, but also haven't had any bad landings with it.
http://www.rcuniverse.com/forum/atta...mentid=2052623http://www.rcuniverse.com/forum/atta...mentid=2052624

When do you expect to start assembly thread?
Gary

A couple of "different" things on my Inspire:
- I decided to try the Gator adjusters that accept the 8mm tubes on BJCraft wings. They are slop-free, were easy to mount, and are lightweight. Only issue was a need to shim them so that they are parallel to the fuse centerline rather than the tapered sides. (this is true of the traditional Gator adjuster too) The picture shows them mounted, but I later added a piece of honeycomb across the fuse width that serves to make the sides more rigid in this area and also serves as a radio tray.

- I used the new Contra mount by BJCraft. It was well worth the $75. It saved a lot of time coming up with a firewall template. Best of all, the unit and motor can be pulled out the front of the plane. Thrust adjustments can easily be done by adding washers in the right location(s). A couple of pictures of the motor and mount are attached. Took me about 2 hours to install the motor!

I like the new hatch latch so far. Much more of a positive engagement than the Episode latch.

http://www.rcuniverse.com/forum/atta...mentid=2054210http://www.rcuniverse.com/forum/atta...mentid=2054211http://www.rcuniverse.com/forum/atta...mentid=2054212http://www.rcuniverse.com/forum/atta...mentid=2054213