Suggestion for a good profile kit.

Has anyone had experience with RSM Distribution kits? They have a P-40 profile kit that looks interesting.

I have been enjoying this forum. After nearly 30 years out of the hobby, I am learning a lot.

Thanks,

Jim

The quality of the RSM kits is equal to that of the Brodak kits. Typically Brodak includes an exhaustive Instruction book and plans while the RSM kit simply relies on the plans. I have found the included hardware very good for both manufacturers, so I don't think you could go wrong with either choice.

See Ya

Dumb question, why would the Cardinal need more horsepower than the Tanager? One is 576 square inches, the othe is 579. The Tanager has a constant cord wing with 2 inches less span, the Cardinal has 2 inches more span with a tapered wing. We flew our 35 regularly with 570-580 square inch planes and thick airfoils, and it does a fine job on that size plane. It has more power than the K&B 40 which is what was used as the powerplant on the prototype Cardinal. Anyway, all that aside, I just happen to like the Cardinal better, although either should be a good choice. The Tanager is $10 cheaper and that may sway the whole argument. But then, one could also opt for the profile Oriental. Choices, choices, but they are all good choices.

Using purely subjective comparisons, one of the sweetest running traditional engines, the ST .46 is no more powerful than one of Leonards reworked OS .35's. Lew Woolard's Silver Foxx .40's offer more power in my opinion, and the OS .40's as we have been modifying them come close to equaling them, again in my opinion. What this is leading to is that comparing apples to oranges doesn't work.

The often maligned McCoy .35's were capable of putting a 610 sq inch Electra thruogh it's paces in the 60's. It's true that they moved up to the McCoy RH .40 as soon as they became available. I personally have flown my first Electra with an OS .35s, to a respectable high placing at the VSC. Ray Firkins' Electra, which placed 3rd. last year at the VSC is also powered by the OS .35s. The Electra has 610 sq inches of wing area and a thick airfoil.

Most of the Pathfinder Profiles that we've flown here, are powered with an OS.40. the early ones were 640+ sq's and they managed to win or place at a lot of contests.

The real key is to do as you should do with a competitive airframe, build it light, straight, and as stong as it needs to be. Extra weight and over engineering, (so it'll survive a less than desirable meeting with terra firma.) are often the reason many good designs never meet their potential and wind up needing to be overpowered. I forget who it was who once passed this truism to me was, but here is the truth about competitive airframes. " Light good airplanes turn to dust when you crash them, if not, you built it too heavy."

So, now to answer the query that really started this thread.

Which kit? of the three, no, four mentioned, let's deal with Brodaks offerings first. They all, as has been noted elswhere, come with extremely good building instructions. The supplied accessorys are of very good quality, and the kits represent a bargain, in my opinion, value wise. Brodak currently has three good kits for that size powerplant.

The Tanager will have no problem with the preferred engine. It, with it's straight chord wing, might be a little bit simpler to build than a design with a tapered wing. It will fly very nicely and work well, bringing a newer pilot up through the skill classes.

The Profile Oriental is similar in construction to the Tanager. It is recomended for many of the same reasons and it's proven abiliy to fly well.

The Profile Cardinal is one of the three best flying profiles I know of in this size range and is perfect for the Pro 40 stunt event as well as being a good backup plane. You can use more power if you wish, but a lightly loaded example of this design can and will fly very well on Len's SS OS .35.

There are some areas that I will make changes when I build my next one. First, I would convert to wing mounted gear so I could get the wheels easily located in the correct position for good hard surface landings. As it is, the wheels are too far forward. But, if you fly on grass all the time then where they are is fine.

There is a weakness in the wire gear mounting as used. Either bush the hole through the fuse that the gear plugs into, or drill another hole above the first one, bush it also, and bend up new wire gear with the plug in legnth extended to a full 1/2 inch. the new gear will have one of the legs agianst the fuselage longer than the other so that one wire will plug into the lower hole and the other will plug into the upper hole.
This mod will allow for much sturdier gear than supplied.

There is a third alternative. Order a set of dural profile gear. (Windy supplies them as do others)

All the options except wing mounted gear, will still have the gear too far forward for good hard surface landings.

Does this mean that I wouldn't recommend the Cardinal? In no way. This is an excellent flying design, and even with this small gear problem, it will outperform most other designs out there.

One Kit that will soon be released by Brodak is the Pathfinder Mk3. At 630 sq's it's an iffy thing with the 35, but 40's should handle it fine. Remember, I'm speaking of modern engines. An ST .46 would be about the minimum size for the older loop scavaged style powerplants.

Rsm's kits are also a reasonable value for the money. The P40 was designed by Pat Johnston. Pat has been flying one on and off for several years, if memory serves me right. It seems to be a good flying plane.

In truth, most any design In the 525-580 sq inch range should work fine with the Stuka Stunt .35.

Just my observations.... the Cardinal, with additional span AND a significantly thicker airfoil throughout, will present more drag opportunities. 'Cause Windy pioneered them, I would speculate that we see more on a regular basis.... While Windy flew his with a DS 40 (primarily), remember that he is a genuine World Class builder (fit) and that the entire fuselage of the 1000 flight prototype was covered with 1.5 oz. fiberglass cloth, stuck with epoxy! Almost all reach 46-48oz., whereas the Tanager is frequently @42.

The weight and drag start to add up.....

See Ya

Here is my take on the plane thing for one of Len's OS .35's - save the .35 for a built up fuse airplane, they do very well on planes under 590 Sq In and 48 Oz total weight. For a profile I would obtain one of Len's Tower .40's. They will pull any profile up to around 620 Sq in and about 48+ Oz very well. That being said, I have a F&B Viking in the planning stages 51" span 550 Sq. in. that I will be using my SS OS .35 in. I also am going to build a profile Cardinal sometime down the line and have actually obtained an OS 40H that I intend to use in it.

I have no experience with the Tananger but I have both a profile Oriental & a profile Cardinal. The Oriental flew very well on a Randy Smith .40 FP/11-5 APC on 62 1/2' OA lines. It flys even better on a bone stock (other than I did remove the head shim).40 FP/Macs tuned muffler/Tornado 10-4 three blade prop on 64 1/2'OA lines. It has scored in the mid 400's with both setups. I'm sure it's capable of much more with someone else wiggling the handle. It did require 2 3/4 ounces of lead to balance it with the stock nose length & the stock engine/Macs muffler. If I built another one I'd shorten the nose or move the wing forward, one of the two. All up it's around 45-46 ounces. The Cardinal "feels" like a much larger airplane, though the wing is actually an inch shorter & only 24 more sq's. The fuse is also much more substantial on the Cardinal. I have an ST.46 on mine & fly it on 68 1/2' OA lines. The Oriental has minimal finish, the Cardinal has .2 oz. CF over all the wood & weighs 56 ounces. The weight doesn't seem to faze the ST.46, it pulls through the pattern just fine, in fact, very well. The Oriental has well over 500 flights on it & the Cardinal has only 57. The Oriental was a marginally easier build since it had no taper to the wings. On either of these airplanes (or any profile) be SURE to glass the wing/fuse joint at least up to the thick part of the wing or it WILL crack, tripler or no! (Guess how I know this.) In fact, the reason I used the CF on the Cardinal was to try to avoid stress cracks in general. In my experience, it's a good idea to completely cover all profiles with something, either CF, glass or silkspan if you want them to last. The Cardinal required no tail weight whatever with the ST.46/small tube muffler. I have only one RSM kit, a Shark 45 that I haven't started on yet. It appears to have very good wood, but as was said earlier, no instructions, although they include very nice plans by Pat Johnston. If you haven't done quite a bit of building the Brodak kits may be a better choice since they do come with excellent instructions as well as excellent plans. Btw, the Cardinal plans were very nicely drawn by John Miller (yep, the same John Miller from above) The Oriental plans were nicely done by Dave Braun. I agree with John on the landing gear setup on the Brodak airplanes. They're pretty shakey as shown on the plans, both on the Oriental & the Cardinal. I went with shortened aluminum Sig Fazer gear on the Oriental & some of Windy's snazzy gold anodized aluminum gear on the Cardinal. I mounted the Cardinal gear so the wheels are slightly behind where it shows on the plans. The gear can then be switched from side to side as well, which moves the wheels back about 5/8ths of an inch farther. I haven't flown it from pavement yet but it lands great on grass. A few things I don't like about Brodak kits is the way they want you to do the pushrod in two pieces with a solder joint & the control horns. I use arrowshaft pushrods & captured ball joints everywhere except the rear of the elevator rod where I use a steel clevis with double locks. I also replace the plastic control horns with brass bushed units.
Nils