Which came first: an RC Model or a full-scale Ultimate?
I started working on this site in response to a question in rec.models.rc.air. The question was which came first: the full-scale or the radio-control airplane? Gordon Price saw the first draft of these pages and sent me some notes and photos. Later on, Devin York contributed a whole folder full of information.
The design of the 10-100 came from Gordon's work on replacement parts for the Pitts. After designing the Ultimate wing kits, canopy, and fairings for the Pitts, Gordon decided to design his own fuselage as well. That was the genesis and birth of Ultiimate Aircraft.
A letter from Don Lowe was published in the late R/C Report (Issue 239, June 2006, p. 38). It's part of "The Big Picture" by Dick Petit. I'm going to break Lowe's letter into pieces comment on each point individually.
Dick Petit ends this section by saying, "There you have it folks, straight from one of the original cast members. It was the full size Ultimate that was developed from a 1/3 scale model, not the other way around. Thanks, Don, for bringing us all up to speed."
I consider Gordon to be "one of the original cast members." He disagrees with the way Don and Dick tell the story. So do I.
-------- Original Message --------
I wrote you sometime back about what I knew about the history between full scale and the model. I finally found the article that I was looking for in Model Airplane News, April 1991. A sidebar was included with a review of the Carl Goldberg Models Ultimate 10-300.
Bottom line, Don Lowe and Bob Godfrey had built a model based on the design drawings of Gordon Price. That model was to act as a test bed for some design changes they thought would improve stability and reduce control coupling. It crashed on the first flight when the elevator began to flutter. Supposedly, Gordon did incorporate some of the suggestions in the full scale but, there were no other models built before the full scale was completed and flying. A 30 % scale Ultimate was kitted by Godfrey's Precison Models after the full-size 10-300 had been completed.
Hope that helps to put the rumor to bed.
I don't have a subscription to that magazine anymore and can't say if they could provide you a back issue or just the article from the archives. I still have my copy and, if I can get it working again, could scan the article in and email.
The 10 Dash Series
"We built kits for 3 types of the ten dash series at Ultimate Aircraft Corp in Guelph Ontario: the 10-100, 10-200 and 10-300. The picture of the 10-300 is from Finland, the 10-100 is the orginal prototype that was badly damaged in an accident, rebuilt and now sits rotting at a junk dealer north of Hamilton, the 10-200 was in Ontario but I have lost track of it. We had some great people working there. It was too bad that I was unable to keep it going. Warm regards, Gordon"
All of the aircraft were designed to use a macro-flap system. 100% throw on the elevators would produce 17% throw on the ailerons to form flaps. 30% of elevator would be accompanied by 5 degrees of flap.
10 Dash 100/180
The 10 Dash 100 was designed to take a 100 HP Continental O-200, 150 HP, or 180 HP engine. Builders could fit any of the three engines by trimming the cowling and installing a new engine mount. The gross weight with a 100 HP engine was 650 pounds (!).
"The 10-100 prototype was last seen on hwy 6 on the west side of the road north of Hamilton. [It's been sold to someone in Ohio (2006). Photos here.] The owner was and maybe still is, Ken Gamble. He has a landing strip on his farm. He bought the aircraft for around $1500 at a bank auction about 1990. The 10-100 was a marvelous airplane but tough to fly airshows because of the limiting horsepower. I managed to fly the Capital Air show with it on July 1, 1986 or 1987, I think. I remember it was tricky to maintain altitude and fly over the Ottawa river behind the parliament buildings. When I flew the Sun and Fun Airshow in Lakeland Florida, I managed to eke out 3 vertical rolls before beating a hasty retreat for speed from the top of a hammerhead. It rolled at 360 degrees per second. A real performer on 100 HP but as I say quite difficult to fly and conserve altitude due to the lack of power ... you just can't have everything. All airplanes are a compromise. The landing attitude and lack of visibility contributed to the landing accident (mid air) and some serious injuries to a friend of mine. The trip to Sun and Fun in a skidoo suit with chemical hand and foot warmers and minus 30 degree temperature is another story. Some stuff I don't miss."
January 8, 2006
Devin York reports that the 10-100 prototype hit a 172 on landing. That must be the "mid-air" that Gordon refers to. But it was repaired after that and was in flyable condition when it was sold in 1990.
10 Dash 200
10-200, last sighted in Ontario.
The fuselage of the 10-200 was 6 inches longer than the 10-100 (17' 4").
For those short on cash, the 10-200 could be built for a 180 HP engine
10 Dash 300
The fuselage is 3 feet longer than the 10-200 (21'?).
Designed for a 300 HP engine.
American 10 Dash 300
The caption reads: "This Canadian-built Ultimate 10-300 "DYSLEXIC" is owned by Bill Baird, Sturgis, Kentucky, and flown by airshow pilot, Nick Smith, Crossville, Tennessee..." [N6521R was 'substantially damaged' in July, 1991, when the pilot ran the lower tanks dry and didn't have enough altitude to restart the engine after switching to the top tanks. Cf. NTSB Report.]
Gordon was asked some questions about this design by a builder.
1) What was the empty weight? Heavy IO-540, or light?
The most important item on any aerobatic aircraft is weight control. The lighter the better. Bezak painted the instruments on his Zlin in 1960 to save weight. Forget the radios, fancy instruments and building for comfort. If it is a true competitive airplane it must be light.
I cannot recall the weight of C-GILB but it was heavier than I wanted because it was a prototype. The engine was a light 0-540 260hp hot-rodded to 325HP on the dyno.
2) Where was the CG? Was it too far aft?
Again, I cannot recall specifically but I think 25% MAC is was our target.
3) Were all of the 10-300's the same? How did they differ?
The first 10-300 was a traditional rag wing and did not have the same performance as the 300S which had the plywood wing. I remember a fellow by the name of Stanislov from the Sukoi design bureau studying my aerofoil carefully and noting the soviet pilots were complaining about their existing wing. I don't know if they changed their design but he indicated that it would solve their problem. There is a picture of the 10-300 on your site on the cover of trade-a-plane [see above]. The Finish airplane and my airplane were pretty well identical. Probably a little on the heavy side.
4) Were there any differences between the 20-300S & the 10-300S other than the additional seat area?
We never did complete the formal design of the 20-300. David was working with Terry Dieno in Saskatchewan from drawings that we had at the time. [The Dieno/LEA plane has been sold to a pilot in New Hampshire in 2003. Stay tuned for a pirep when he and his friends get it flying.]
Essentially the only change is the additional seat. I don't recall a longer fuselage. The second pilot was very close to our target MAC which did not cause much change in design.
5) How did the 10-300S snap? Was it a good-snapping airplane? Any special techniques?
The 10-300 was designed for the judges. We then had to make it fly for the pilot. The long lines gave it the same visual characteristics of the monoplanes. If you were straight, there was no doubt. If you were 5 degrees off there was no doubt. Whereas with a Pitts you could fudge a few degrees but the judges never accepted it for drawing crisp straight lines because of the visual fudge factor.
The full scale 10-300 series is longitudinally stable which is a disaster for the aerobatic pilot (but a delight for the licensing authorities). The stick loads are unbearable without some sort of assist. Our solution was the integrated control system which provides for 5 degree full span aileron (flap) movement opposite to the 30 elevator deflection. Pull back and the ailerons droop. Push forward and the ailerons go up. And presto! the corners were sharp and stick loads were manageable.
The snap is a horizontal spin. To spin the airfoil must be stalled. A high speed stall after inducing a skid makes the airplane "snap." Flaps reduce stalling speed. So in effect we have a contradiction. We try to stall by pulling or pushing but the effect is counteracted by the action of the 'flaps' which is trying to prevent the stall. So does it snap well? Yes?.
For a positive snap a good sharp pull satisfies the judges as they see the positive pitching of the nose, then you ram the stick into a forward corner (removing the lift) and the rate of rotation is magnificent. It took a little getting used to but it was a fabulous snapper. I remember that the YAK-50 did a fabulous outside snap but stopping it was a problem since the stick remained in the forward corner unless forcibly removed. This was due to a large lead counterweight on the elevator inside the fuselage. But I digress.
6) What are your thoughts about the "S" wing performance characteristics vs. the original airfoil? My observation (only by looking at them) is that the original airfoil would provide better snap characteristics and climb rate.
The "S" wing would provide more speed. It is a toss up. The S wing is faster and I think better, but it is heavier.
7) What was the max rate of climb?
Quite variable really depending on WAT [weight, altitude, temperature] and humidity. A light airplane has a better rate of climb.
8) How much vertical penetration?
Again variable. It depends on the ability of the pilot to conserve energy using optimum G loading and gentle control input at low speeds. It was adequate for any unlimited manouvre.
9) How many vertical rolls?
Sorry again variable depending on positive /negative fly-away, push, pull, hammer, torque or spin.
10) What was the roll rate?
360 degrees per second.
11) Did the full-span ailerons create a lot of drag or adverse yaw during multiple rolls?
No doubt there is adverse yaw but it was easily compensated for with proper application of rudder.
11) What was knife-edge flight like?
Knife edge was good left only if I remember correctly. I did develop a 'knife edge spin ' which was the most disorienting manouvre I was ever in. Wild is the word. I performed it once publicly at the 1988 CNE airshow in Toronto in the haze over Lake Ontario.
13) Rob Holland's (Terry Dienno/ David Lea) 20-300S has 2 inch bands of Kevlar cloth wrapped around the longerons approximately every 12 inches from the seat back to the tail post. Is this enough bonding area? How were the skins in your 10-300S bonded?
I can't recall. Our intention was to remove the steel structure and beef up the kevlar to reduce weight, but we never got that far.
14) Are the any changes that you would have made to the 10-300S if you had more time?
Lots but it would be empirically designed and tested as we gained experience.
15) While we were unloading the 20-300S, I noticed that the horizontal stab just barely fit into the truck trailer. Did you design it to be this way, or was it just coincidence?
I wish I could say yes but in all honesty the mating with a trailer did not enter my mind.
A final word of advice for test pilots:
Be careful and stay over the field. I was always very cautious when testing and it paid off a number of times. Also the airplane will not kill you but sudden contact with the ground will. Come close to the ground only on landing. I have a lot of dead friends.
Twenty Dash 300
Design of 20-300
"Enclosed a copy of a press release in 1987. Unfortunately we did not get a 2 seater completed before the demise of Utimate."
|In my first version of this page, I had reported that Gordon Price seriously injured himself and a 10-300 in 1991. This is false. Here is the NTSB Report. The airplane type is a "Gordon Price Ultimate," and it was built by him, but he was not the owner nor the pilot of the crashed airplane. Here is the NTSB report:
NTSB Identification: BFO91DLQ01 .
The docket is stored on NTSB microfiche number 48106.
Accident occurred Monday, July 29, 1991 at FRANKLIN, KY
Aircraft:GORDORN PRICE ULTIMATE 10-300, registration: N6521R
Injuries: 1 Serious.
THE PILOT WAS EN ROUTE AND AS HE WAS SWITCHING FUEL TANKS, THE ENGINE LOST POWER. THE PILOT MADE A FORCED LANDING IN FIELD WHERE THE AIRPLANE WAS SUBSTANTIALLY DAMAGED. THE INVESTIGATION DID NOT DISCLOSE EVIDENCE OF MECHANICAL MALFUNCTION. THERE WAS FOUR GALLONS OF FUEL IN THE TOP WING FUEL TANK AND NONE IN THE FORWARD AND AFT FUSELAGE TANKS.
The National Transportation Safety Board determines the probable cause(s) of this accident/incident as follows. DELAY IN SWITCHING FUEL TANKS WHICH RESULTED IN FUEL EXHAUSTION AND LOSS OF ENGINE POWER.
Gordon wrote me to set the record straight:
>Gord Morning Marty,
>One quick note. It was not I,
History of the Ultimate Design--Pitts Special Team
This site has some nice line-drawings comparing the 10-200