Blackhorse bird dog - rc setup

[Kevin Osman]

Hi,

I have read the review of the Blackhorse Bird dog and would like to understand what the final settings of the test model regarding aileron differential and aileron to rudder mixing were.

It mentions "more differential" and adding some "aileron to rudder mixing" could you please inform me what these settings ended up as?

I have also seen stated that the c of g is incorrect in the manual. If so does anybody know the correct value? I have put a saito 72 engine in my model which was advised in the review but it is a lot lighter than the 90 size 4 stroke you had. Is this going to cause me a problem?

I saw in a video from the states that you can buy a harry higley heavy hub. Does anybody know where in the uk it can be bought? or is there the same thing from another supplier?

My model is close to completion and these questions are key to me taking the plunge on the flight line. any help will be greatly appreciated.

[colin nolan]

Hi Going off my memory of the review model I increased the aileron differential by 2mm or so,and programmed in an aileron/rudder mix of 5%.I had the receiver battery as far forward as it would go and still had to add lead to get the C of G correct.This gave a much nicer feel to the aircraft and totally eliminated the skidding into turns that were prevalent beforehand.The Thunder Tiger 91 that I fitted was definitely too powerful,and as I said in the review,I think the 72 will give a much better balanced flight envelope.

[Tim bennett]

Hi ,

Kevin the Bird Dog flew a treat, I did some work on it but mainly cosmetic, moved the throttle servo back into the cockpit , put a 6v batt pack in for the rec as it is on 2.4ghz, took the lead off the cowling and melted down a nice weight and bolted it to the fire wall.

The Saito 72 flew it perfect with power to spare, I had to change the wheels as they were a little small and on landing the under carraige was acting as a brake, I will try and get some pictures next time it goes out.

Cheers

[Martin Whybrow]

On Kevin's point, where should the CofG be? The printed manual and the downloadable manual, both the same issue if you can believe what it says, give different values and I have also heard that the value in the manual is wrong. Mine's in storage pending a house move, but I want to maiden it when the move's done.

[Flyoz]

I also would appreciate some clarification re the correct CofG as Im about to maiden my BD.

Also I set the Aileron Differential to 20mm up 7mm down per the manual but it looks a lot to me??

[Keith Evans 3]

Hi I have just built and test flown my one sixth scale Bird Dog from a Model World plan.The plan shows a C of G range between 16 and 28 % of wing chord.I set it at 25% and there were no problems. It was fitted with an O S 55 AX . Plenty of power but it needed ton of lead up front to get the C of G to this position .Hope this helps.

[Flyoz]

Thanks keith thats about the 80mm Blackhorse recommends.

To achieve that balance point I put the battery and some lead up front just at the rear edge mark of cowl with a Saito 72

So I'll see how it goes

[Flyoz]

Well after the 6th test flights and rebuilds I manage to get it away but the left wing dropped so much it needed full right aileron.

It was also way to tail heavy although it balanced ok at the suggested COG points. I reckon an inch or 22mm fwd of the stated 80mm from LE would be better. And down she went.

I had used less lead after adding a bracing firewall after a crash and now remember the maiden needed full down elevator to fly right so the stated C of G was always wrong (made worse by using less lead later).

The two wafer thin main beams 2mm X 45mm "communion biscuit wood" thru the nose also just allowed the complete nose to fall off after a small knock - even a backfiring 4s might have broken it! ( i had to add 4 3/8 sq beams to strengthen the nose).

All in all the BH BD looks great with decent fittings but is flimsily made and the C of G is wrong.

The butt/ interlocking cheap ply pieces are suited to a light electric NOT an 80" Glow model.

[Tim bennett]

My Bird Dog fly's spot on Saito FA 72 fourstroke, balanced as the instructions say and all controls set up as the instructions, small amount of lead up front but not much , ideal trainer in my opinion, been flying for well over 35 years, the Saito has plenty of power and she looks and fly's very scale.

Airframe is also built well, infact when I look at some of the newer artfs I think it's stronger than most.

It's also up for sale ready to fly if any body is interested, selling as it's my last nitro plane all my others are now petrol.