Terrier (oz6559)


Terrier (oz6559) by Al Clark 1984 - plan thumbnail

About this Plan

Terrier. Radio control sport model for .25 power.

Quote: "Third in a series of designs which have been refined to get the best performance from a standard .25 engine... the size of most .40 and some .60 aircraft, but uses a standard economical .25 engine. I used the OS .25 (non-Schneurle) on my Terrier because it idles very slow and will run about eleven minutes on four ounces of 10% nitro fuel.

Take-offs are easy - just gentle rudder input to steer, hold about 1/3 back stick and the Terrier will do a beautiful, smooth take-off every time. If you like the hot dog type, just let the tail come up, steer with the rudder until you are really moving, then haul the stick back and you are off! Remember, on this kind of climb-out to hold some right rudder - you will need it.

Aerobatic maneuvers of all kinds can be done with the Terrier. It will do the usual loops, rolls, spins, snap rolls, and hammerheads with ease and, with a little practice on your piloting technique, you will be doing 4-point rolls, tail slides, double snap rolls, snap on top of loops, square loops, and many others. Due to the Terrier's slow flying speed and low stall speed, you will be able to do all these maneuvers right in front of you! No more far away turnarounds setting up for the next maneuver.

In addition to these maneuvers, you will be pleased to discover that the Terrier will also do a lot of outside maneuvers. Outside loops, outside snap rolls, outside loops with outside snaps, and inverted spins are all easily done with the Terrier. Spins and snaps, both inside and outside, can be stopped very easily merely by releasing the controls. Low and slow flying is easy, using a nose high attitude and 1/4 to 1/3 throttle..."

Scanning by Don at EAC, cleanup by theshadow.

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Terrier (oz6559) by Al Clark 1984 - model pic


Terrier (oz6559) by Al Clark 1984 - pic 003.jpg
Terrier (oz6559) by Al Clark 1984 - pic 004.jpg
Terrier (oz6559) by Al Clark 1984 - pic 005.jpg
Terrier (oz6559) by Al Clark 1984 - pic 006.jpg
Terrier (oz6559) by Al Clark 1984 - pic 007.jpg
Terrier (oz6559) by Al Clark 1984 - pic 008.jpg
Terrier (oz6559) by Al Clark 1984 - pic 009.jpg
Terrier (oz6559) by Al Clark 1984 - pic 010.jpg

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User comments

Hi Steve, Glad to finally see this fine RCM plan available on your wonderful site. I built a Terrier from scratch (including scaling up & drawing the plans right from the magazine page) nearly 20 years ago. Still have it, fully intact after wearing out the engine. Wonderfully easy to build, and a superb flyer with an O.S. .25 FP engine, 9x4 or 9x6 prop and 4 standard size servos. Would probably fly ok on a .19, but would probably be overpowered with anything more than a hot ball bearing Schneurle ported .25. Definitely don't recommend trying a .40 on it. Would probably make a great electric conversion without deviation from the plans, as the construction is quite robust yet very lightly built. Mine flew straight right off the building board, requiring nothing more than 2 clicks of left aileron trim. Two circuits around the flying field to get a feel for the response and then proceeded to put it through every aerobatic maneuver I was capable of on it's maiden flight. Low landing speed with no tendency towards tip stalls. Absolutely no evil tendencies in this ship. After a wonderful write up like this, I need to rebuild the engine and put mine back in the air! I highly recommend this plane for anybody who is competent with a basic 4 channel trainer and who is looking for a good mid-sized sport plane. I'll take a photo or two of mine some time this week and send them in to add to the plans.
BillyMcCaskill - 19/04/2015
When I saw this plan in RCM I ordered it right away. I liked Al Clark's design philosophy and the look of the model. It was my first "scratch" built plane [see more pics 003]. Four stroke model engines were new and I had this brand new O.S. 40 four stroke which had about the same horsepower as a standard 25, so that's what I used. I moved the firewall back 3/4" to compensate for the added weight of the engine. I'd like to say the plane flew but a radio problem ended the flight right after take off. A few months later two of my modelling friends and I got together and in one Saturday morning we "manufactured" parts for 3 planes. The plan was to show up at the club meeting with all three models on the same night, which we did. The response was great. My Terrier, with the 40 four stroke flew just great. It was a little heavier with my engine choice but it made beautiful low & slow passes with that 4-stroke sound. It also made beautiful hammer head turns. One bystander said that after seeing my Terrier fly he was going to build one. After several years of flying Terrier number two it was lost while trying to perform a 1/2 loop from inverted resulting in a "figure 9". It was such a nice flying plane I had to build another one. The third Terrier was built and I flew #3 for about 5 years [see more pics 004]. When I brought it out in the spring I found I had to replace the fin and horizontal stabilizer because of warping over the winter. On its maiden flight after the repair the stab folded after a loop and that was the end of #3. When I built #3 I made a second set of parts which I still have. They have been calling to me for some time. I still have that trusty old 40 four stroke.............. I have also thought it would make an great electric conversion.
MikeHausner - 08/10/2015
Steve/Mary, here are pictures of my Terrier [more pics 005, 006]. I just wanted to add my support for this great plane. O.S. FS.40, Polyspan covering.
JimHales - 06/06/2017
It's a pleasure to welcome Elvis to Outerzone! [more pics 005, 006]
Mary - 06/06/2017
The Terrier was probably the first aerobatic model that I built, in the 80's I think. It was a fine handling aircraft with no vices, a real pleasure. I wish I could remember what happened to it but that is what ageing does to me.
Fred - 14/06/2020
Three new additions to the club fleet [pics 007-010]. They have lived up to the previous comments and with very little trimming have been a pleasure to handle. In the photos attached the middle model belongs to our President who has actively promoted the design. The one on the left was its maiden flight today and the other is ready to go very soon. Other members are keen to join the fleet and these should feel the wind very shortly. To Outerzone and Mr Clarke we thank you for a great service to the model flying community. To a large number of modellers in New Zealand this service is very much appreciated.
Colin Firby - 28/12/2022
What a nice airplane! I built it 2022 from Outerzone plans and I have now over 11 hours flight. Easy to build and to fly so I can really recommend this plane. Engine is a Saito fa 40. [see main model pic]
Peder Olsen, Sweden - 30/01/2023
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