rglgatortail

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Has anyone bought these plans from the magazine Radio Control Modeler Plans Service? I bought these plans about four or five years ago and finally got around to building this little plane so I can have a scratch build under my belt. What I did was that I borrowed a few building techniques from building a few of Great Planes Ultra Sports and so I ended up a real nice flying plane. I did deviate from the plans from the way the wing is built by building with wing spars and leading edge sheeting creating the "D" tube wing, and on the fuse I used a canopy that my Dad asked me to use and a pilot to go under the canopy but in order to do that I had to build up the fuse a little bit more by adding more balsa material to meet up to the canopy. After I sanded a couple of tear drop wing tips, the final wing span measured out to 41-3/4 inches, the all up weight ready to fly came out to 49 ounces. Power is by a OS 25 FX and Futaba servos for flight controls and a micro for the throttle. Questions and comments are cool and I would also like to see if anyone will rate a comment on my plane in my gallery.

Rodney

You did a fine job of kit bashing, that is the way to go. To many people are afraid to try this. Looks like all your changes were smart ones.

BMatthews

It looks cute as a bug's ear with that canopy.

I hesitate to rain on your parade but watch the slow speed stuff until you get used to flying it. 49oz for that size is a bit heavy and you're likely going to find that it shows up in the need to keep the speed up higher than you may like in the landings or for slow and low flying. Mind you with that engine you certainly won't notice it during takeoff and climbout! ! ! !

kdc

It's called a Slycat isn't it? A design by the late Harry Gilkes of Coventry England. He made a number of designs with CAT in the name ( stands for Coventry Air Technology or something similar ) all were very slim and most were solid canopies, not glazed.
Original weight is said to be 47 -52 ounces so 49 seems OK

A fine model and better looking than the original, but maybe a little more work.

BMatthews

Really on the weight? Seems a bit high to me. But then a lot of the Brits seemed to like overbuilding from what I saw in a lot of the RC model plans from the old RCM&E magazines.

kdc

I dont really think RCME / British designs are heavy, and I always thought american designs were heavier! Presumably its the Canadians who build lightest! Actually most US designs for built up wings use fibreglass on the centre section. Virtually no British designs use fibreglass reinforcement except for foam wings. Which accounts for our lighter models.

This model is just about 3 pounds which seems OK for a .25 engine. The exact sq inches is not given in the article but measuring the small plan seems to show a chord of 9.2 which gives about 420 sq inches. So about 16 ounces / sq foot. Seems very good to me.
( I suppose we are talking the same ounces? Its the 28.3495 gram ounce which is 16 ounce to the pound. Only the fluid ounce is diferent so 20 fluid ounces makes a pint in Britain ( drinkers beware! ) which makes British pints & gallons bigger than US)

kdc

Actually I have just found the orignal RCM advert for this plan and it's only 350 sq inches / 2.43 sq ft. So at 49 ounces its actually about 20 oz sq ft which makes BMatthews comments very relevent. It should still be an excellent flier though as the designer published several similar plans such as Cat25 ( Radio Modeller May 94 ) with slightly more span 44.5 inch & 8.25 chord. There is also a smaller version called Alley Cat at 35 inch span but it is mid wing ( Radio Modeller July 92 )

BMatthews

20/sq foot is certainly higher than I like to have on a model of this size if I'm flying it. But it's not unflyable by any means as long as the pilot gets to know how it likes to be handled. 15 to 17oz/sq ft produces a far nicer flyer that slows down nicely with few or no bad traits yet is still "heavy" enough to fly well in blustery conditions.

KDC, I've certainly seen lots of very nice and light British designs presented in the RCM&E as well a Flying Scale Modeler on many occasions. But it just made it that much more odd when I ran across some of the simpler "Stik" style general sport designs that just seemed to be vast lumberyards of thick blocks and sheets.

Mind you as you say the American mags did produce a few of those as well.

rglgatortail

My Feedback: (7)

Thanks for the comments guys I appreciate that. I really didnt think that a 49 ounce (just a smidge over 3 lbs) is heavy and the plane flies wonderfully. The engine gives it all the power that I thought that a O.S. 25 would throw it including unlimited vertical climb. If I was to guess a flat and level full power flyby I would have to guess about 60 or better, my friend said he will shoot his speed gun this weekend when I take it out there and get a accurate number on a level flyby. I guess I could have built it on the heavy side with the few changes i made to it, I thought I was saving the weight by making changes to the way the wing was built, but if I was to build another one some day I would change the formers from 1/8 ply to 1/8 hard balsa and the fuse doublers from 1/16 ply to 1/16 hard balsa or light ply, yeah I followed pretty much all of what Harry Gilkes designed it but I did leave out the 1/64 ply tripler that he wrote in for the outside of the fuse because I felt that it didnt need it.

I didnt know that Harry G. made plans for other designs, I looked around and if they are out there he didnt submit them to RCM Plans service. One article that I read was that he had plans for designing several different sizes of the Slycat, its too bad that he passed away before I could see the plans on the bigger sizes of the Slycat. That is neat about the designation of the CAT name, I learn something new everyday.

I have to say I am pleased the way the plane finished out and I am going to enjoy the plane for a long time to come. I will work on a video here I hope this weekend and post a youtube link when I have the video uploaded and some more pictures, my camera battery died so I just took a few with my cell phone.

rglgatortail

My Feedback: (7)

Hey guys I'm getting 16 oz./ft with my weight of this plane so that is a good number in my opinion. It didnt show any bad habbits during take off or landing, but i did experience a bit of coupling with knife edge flight.

kdc

As you have the actual wing dimensions your sq inches figure may be more accurate & larger than the 350sq ins quoted on page 198 of RCM June 96.

As regards Harry Gilkes other designs I found the following

Alley Cat 38 inch mid wing for a .10 to .20 free plan in Radio Modeller July 92 ( published in England now part of RCME )

Cat 25 44.5 inch low wing free plan Radio Modeller May 94

Street Cat 48 inch for a .40 2 stroke plan number RC 410 Radio Modeller Aug 92 plan still avail from MyHobbyStores.co.uk

Cat 500 50 inch one piece model to AMA 500 regs 12 percent wing section Radio Modeller Feb 94 plan no RM450 still avail from MyHobbyStores.co.uk

Aeronca Tandem 60 inch plan No RC 1702 still avail from MyHobbyStores.co.uk in England

and of course the Sly Cat from RCM June 96
All the Cat models are a very similar style construction with cockpit solid and used as a hatch.

copies of the July 92 Radio Modeller with free plan , Feb 94 & Aug92 ( no plans) are still avail today from a specialist secondhand model magazine retailer. Probably 1 copy only so I wont tell you here but send me a PM & I will tell you where! ( I know of other modellers who have bought OK from the source but I have no connection otherwise )

kdc

There was a slight typographical error in the website and in the plan number I quoted.

Street Cat is RM410 see http://www.myhobbystore.co.uk/produc...m410street-cat

I also found the article for his 60 inch Aeronca Tandem its in RCME Jan 93. Again a copy of the magazine is advertised for sale at the moment ( no plan in the mag you have to buy that from MyHobbyStores )

rglgatortail

My Feedback: (7)

That is interesting to see that thankyou for sharing. I also find it interesting to see that a hobby shop in the UK has these plans. I wonder what the price conversion is to United States dollar is ill look it up later. I have this build under my belt I dont feel like building another plane from scratch for awhile because I need to find me a job first. From what I can tell the Street Cat is just a larger of my SlyCat so if I need to I can go to a local business close to me and ask them to blow up the plans to get the wing span at the 48 or 50 inch span. Thanks again for sharing this. I have plans on getting some video and more pictures of my SlyCat tomorrow so look for them here in the next couple of days.

kdc

You are somewhat mistaken about MyHobbyStores!
They are not a local hobby shop but the publisher and plans department of RCME and it's USA version RC Model Aeroplane. All the old Nexus/Argus/MAP/Magicalia/Highbury magazines including Aeromodeller, Radio Modeller & RC Scale aircraft etc have their plans here. As they publish a special version of RCME in USA called RC Model Aeroplane they have a USA telephone number 1- 877 230 2998.
As the exchange rate is now about 1.59 US dollars to pound you need to multiply the pound price by that.
Each model has subtle differences in many details so Street Cat is not merely an enlarged version although they look similar. The Street Cat is rounded somewhat like your version of the Sly Cat so looks nice. In some cases the wing section is quite different.

There is yet another Gilkes plan called Cat's Paw which is 32 inch for a .10 to .15 and is low wing. A free plan in Radio Modeller Oct 93 (again a copy is avail secondhand with plan for 2 pounds ( about 3.20 dollars )from the source I know of )