Before it was Rare Bear

[Big_Jim]

Re: Before it was Rare Bear

Keep in mind to keep from cooking ignition coils and other items under the cowl a blower setup was devised for forcing air through the cowling after a run once the engine was shut off on the ground.

Huh. I wonder why Rod Lewis' bunch never utilized that idea?

OH, that's right, they were offered. But...."We think our way works just fine".

[BellCobraIV]

Re: Before it was Rare Bear

In another thread a comment was made about Sea Fury's and three blades. I thought it was important to answer the question both there where the original question was asked and here because of the history continuity. So please forgive the double posting;

QUESTION FROM RAD2LTR
"I'm still curious why none of the Sea Fury guys tried running a 3 blade like Bears. I'f I'm not mistaken, there is one hanging in Sanders shop on the back wall. Yes it was a handful on a Bearcat, but a Sea Fury is a whole lot more airframe to absorb the harmonics ect. I can only wonder how fast September Fury would have been with it. (It would have looked awesome as well.)

Will"


ANSWER;
"Will,
Quite simply there never was a "3 Blades R Us" store. The design wasn't a resurrected World War 2 development program. It wasn't an experimental NACA program. The 3 blade propeller was designed in the minds of Carl Friend and Dave Cornell. Dave left the team the day after the surplus P-3
Orion blades were purchased for the project. We still had the research notes for the project and Carl Friend's input.

The 3 blade propeller modifications were proprietary, we took the modifications to the propeller shop. California Propeller Service did not come out and say, "Hey, we have this really great idea and are you interested?" No in fact when we approached them to build a propeller consisting of modified P3 blades with modified cuffs to clear the cowling based on using a 3 blade Constellation hub with specially created spacers so the blades would fit the hub Cal Prop thought about it quite deeply.

Finally Barry agreed to build and maintain the 3 blade for a fee with a planned ongoing inspection program. Part of the agreement required every one of my Lyle's closest living relatives to sign a release of liability in case of failure. They didn't want to be in the 3 Blade racing propeller business, plus it wasn't theirs to offer copies of. It was ours exclusively we assumed the risk, we got the rewards. Lyle never complained of the handling when he raced the plane. Point of fact as the crew we didn't have any inkling until John Penney brought the situation up. Lyle just used it because it went faster for the same power.

Bill Prewitt made the spinner backing plate out of billet aluminum and the carbon fiber spinner was made in-house by one of the fabricators of the B-2 Spirit prototype team. (We didn't know that then because nobody knew what a B-2 was) both the spinner and backing plate were designed to match the 4 blade diameter because the cowl opening and the afterbody were considered by now to be optimum.

Keep in mind to keep from cooking ignition coils and other items under the cowl a blower setup was devised for forcing air through the cowling after a run once the engine was shut off on the ground.

So in short the Sea Fury guys weren't ever offered one."

[wingman]

Re: Before it was Rare Bear

Greg Shaw and Dwight Thorn -- Reno 1989

[BellCobraIV]

Re: Before it was Rare Bear

I'm sure glad the thread is still moving along. Probably a bit slow and meandering for the Millenials among us, but working pretty good in Geezer time...

In the picture with the cowling removed on the left two things come to mind, the first is how well the fit of the spinner and the afterbody was. There were the distributor caps that protruded, the lower sump protruded as well, keep in mind all those little access panels were sealed with a sealant to control the airflow leaks. Notice the extremely nice fit of the little plates around the propeller blades.

The second item is that is Rich Donahue working on the exhaust system at the races. Rich had helped Dave cut and shape the exhaust pieces and quite often could see a particular pipe and know better than most where it went and what order they fit in.

At this point I think that it is really important to point out that in actuality Greg Shaw was a much better Crew Chief than Dave was. Greg was not quite the idea person that Cornell was but he could handle a group of people extremely well. I had the privilege of working under Bill Hickle, Dave Cornell, Greg Shaw, Bill Kerchenfaut and L.D. Hughes among others in a crewman relationship among others. All of those mentioned were exceptional, however "Kerch" and "Shaw" knew how to get the best out of the people on the team.

[wingman]

Re: Before it was Rare Bear

I'm sure glad the thread is still moving along. Probably a bit slow and meandering for the Millenials among us, but working pretty good in Geezer time...

The next and most secret part was to optimize the back pressure to exhaust outlet velocity by machining rings that were shaped and sized in a manner that would make the best use of the pressure cowl design that Dave and Bill Prewitt were installing based on the DC-7 cowling. Bill was an excellent sheet metal fabricator and was able to bring to reality the design Dave envisioned.

The spinner off a Bristol Beverley was adapted to the four blade propeller and we were able to close down the gap between the spinner outside diameter and the cowlings inside diameter to a ridiculously small looking dimension. Without proper exhaust augmentation the engine simply would not have had enough air going through the cowling to cool the engine. A metal plate system was developed to increase the venturi effect between the higher velocity exhaust gasses and the slower cooling air. Ultimately flight tests showed that at speed the "flat plate" area between the gap of the cowling and spinner was negated to near net zero. The spinner afterbody that was fabricated by Prewitt under Cornell's direction shaped the airflow to get the maximum use of the air going through the cowling. To finish the package the baffles were installed using silicone sealer to control the airflow better. High temperature rubber pieces were installed to manage the airflow at the cylinder base gaps.

Torque meter readings showed that the augmented improved exhaust system was good for close to 300 horsepower, the engine cylinder head temperature was reduced and flight test numbers showed a significant speed increase due to the reduced drag.

So a really good system started by Cliff Putnam was perfected and included in a package of air/engine management thought up by Dave Cornell brought to life by the metal shaping magic of Bill Prewitt. Rich Donahue gets credit for training the exhaust pipes to fit as needed. Lief was correct, working on the exhaust was a Bearcat kinda deal.

[AAFO_WSagar]

Re: Before it was Rare Bear

From the first time I ever had the opportunity to get to know Neal, it was in Jack and Sylvia Sweeney's motorhome at a race. But early in the week before things got going I looked forward to visiting and talking to Neal. I never felt like in our conversations that there existed a disconnect between us and always felt he understood the depth of the work we were doing. It's one of the reasons I ALWAYS enjoy the game of show and tell with you Neal. I always feel you understand.

Hey John, as I said in my response to Neal, for sure I know he knows LOL.... I was just talking about how much I like fixing stuff and even more, keeping stuff new! My old Silverado is a pretty good example of how, with a little care, you can buy a vehicle new and pretty much drive it till you're dead!!

Thanks to both of you for keeping this thread alive... John, I think you know how much my time with the Bear and knowing Lyle means to me... I have to pinch myself that I could call Lyle and he actually knew who I was and usually made time for me... In my mind, that man was the greatest air racer EVER.. it was in his blood. Hard to describe but you just felt it being in his presence and mind you, I only knew him in his golden years! God, I wish I could have met him in his prime...

Special man!

[AAFO_WSagar]

Re: Before it was Rare Bear

I certainly know how to do it -- I grew up seriously poor and for many years never had jobs that paid much. I worked on my motorcyles and I worked on my cars. I hated it! One of the happiest days of my life was when I figured out that I had enough money to pay other people to work on my cars. I really prefer taking pictures, and luckily I'm a lot better at that than I am at fixing cars...

Grew up poor as well, pretty much on my own from 11 years old on... Lived with my dad, but he was more of a very good OLD friend who guided me, rather than aimed me at anything.

The MDTA thing was just a way to get some "government money" back then for those of us who did not finish high school.. but truly, the lessons learned in that one year of education totally changed my life.

I pay someone sometimes to do stuff but invariably, they do not do it to my standards! Particularly with fiberglass body work...

**sigh**

Anyway, I hope you did not think I was diminishing you in any Neal!! I know you have great depth of mechanical knowledge about the racers... you were the fly on the wall then after all!

I'm very fortunate to have been that fly a couple times myself, very fun spot to be!

[BellCobraIV]

Re: Before it was Rare Bear

I certainly know how to do it -- I grew up seriously poor and for many years never had jobs that paid much. I worked on my motorcyles and I worked on my cars. I hated it! One of the happiest days of my life was when I figured out that I had enough money to pay other people to work on my cars. I really prefer taking pictures, and luckily I'm a lot better at that than I am at fixing cars...

Neal

From the first time I ever had the opportunity to get to know Neal, it was in Jack and Sylvia Sweeney's motorhome at a race. But early in the week before things got going I looked forward to visiting and talking to Neal. I never felt like in our conversations that there existed a disconnect between us and always felt he understood the depth of the work we were doing. It's one of the reasons I ALWAYS enjoy the game of show and tell with you Neal. I always feel you understand.

[wingman]

Re: Before it was Rare Bear

I certainly know how to do it -- I grew up seriously poor and for many years never had jobs that paid much. I worked on my motorcyles and I worked on my cars. I hated it! One of the happiest days of my life was when I figured out that I had enough money to pay other people to work on my cars. I really prefer taking pictures, and luckily I'm a lot better at that than I am at fixing cars...

Neal

[AAFO_WSagar]

Re: Before it was Rare Bear

Stuff like this makes me glad not to be a mechanic.

When I was in my late teens, early 20's, I entered a government program called MDTA at the time, short for Manpower Development Training Act.. They offered the going unemployment weekly stipend if you committed to and kept your grades up in a training program.. I chose auto mechanics. I learned so much from that year in Community College that it affected the rest of my life. Virtually everything I've done since then has had mechanical knowledge involved..

Yes, it can be EXTREMELY frustrating at times, but ultimately satisfying when you solve a problem or even better, come up with a "Make it better than before" solution to a problem...

I've gotten along pretty well with most of the mechanics/crew on air racers partly due to I know about what they do..

You should try it sometime Neal... LOL!!!!

[knot4u]

Re: Before it was Rare Bear

The folks that took over the "The Beatles instruments" never understood why different people couldn't make the same music. Cornell understood where the music came from and was able to produce good results. When the airplane went to Texas they didn't understand what they had, so they went flock shooting and slowed down the Fastest Piston engined airplane in the World. They prioritized a new exhaust system, they prioritized adding 3 additional dyna-focal engine mounts to the existing engine mount. A mount that was consulted on with not only the engineers that had designed the early Constellation engine mounts, but they brought in the original Dyna-focal engineers that understood exactly what was required. So they went from the six mounts we had always used to nine mounts which unbeknownst to them was most likely too rigid. But maybe that's necessary when you truck the airplane between Reno and Texas instead of flying it? I don't know?

You're trying to break my heart right? Sure seems like it. I wonder if I'll ever get to lay hands on that airplane again, even if it's just (preferably) to say hello. If it's in a museum I can travel. It was never a mystery where or when we were working on it, the circus of the rodeo used to show up almost constantly. I'm not sure if it was Fred, Gil or Bill that finally put their foot down and made the door opening the deadline. That didn't seem to dissuade anyone, they just set up lawn chairs outside of the hangar and watched us work. That was actual entertainment for some people on weeknights or weekends. After we were done for the evening it wasn't uncommon for us to join the people outside of the hangar and take advantage of their libations and chairs as we'd all sit and look at it in horrible fluorescent lights in the middle of the night and ponder. I'm not sure what we were pondering but we did plenty of it so I suspect I'm an expert ponderer these days.

[BellCobraIV]

Re: Before it was Rare Bear

Removed

[BellCobraIV]

Re: Before it was Rare Bear

So this photo?

That photo shows the brand new QEC sitting on the ground to the left of the plane.

[BellCobraIV]

Re: Before it was Rare Bear

There's also this one -- during the original buildup of the exhaust system?

That was the photo I was referring to in my last post, yes.

[knot4u]

Re: Before it was Rare Bear

So the story is even more complex than I thought. The end result did sound like to a large degree like Cornell thinking but I had no idea how complex the balancing of air coming in and air going out with the exhaust system could be. No wonder the Texas guys seemed to get lost in it all.

Here are a couple of shots from 2002 that show the developed system (or at least another stage in its evolution).

I don't know how many times Fred, Gil and myself took that apart and reassembled it (after work, we all had full time jobs) in a t-hangar at Van Nuys (in the summer at night when it was still 100F, or when it was 30F in the winter, in the hangar). It was all inconel, and as John said fabricated from another application. I recall Greg Shaw brought in an oxy-acetylene setup to look for cracks, he'd take each piece (while it was disassembled) and heat all of the joints up looking for cracks, the cracks were apparent when the part was red hot and we'd send it out for repair. Every time we took it apart we always tried to remember how we'd done it, unfortunately most of the time half of the pieces would just fall out after we loosened a bunch of clamps. This was not uncommon, that airplane would fight you every inch of the way if you were working on it. So despite our best efforts and recent experience trying to reassemble it was always a challenge. Like I said, you'd think you were 1/2 to 3/4 of the way to the finish and nothing would fit and you'd have to almost have to start over. The key was to assemble everything loosely (Hang On Loosely, .38 Special, look it up) but some of the tubes would require tightening before they were made impossible to access by the rest of them, and then it wasn't just left and right because it was a round motor so eventually top, bottom and left and right had to join. And you better not pre-stress any of these pieces because they'd be sure to at least crack, or at worst fail at the worst possible moment and making sure none of them were rubbing each other the wrong way was always a challenge and another reason to start over. Like I said before it was a challenge (nightmare) but once it was installed it worked. It should have been replicated, not replaced.

https://m.youtube.com/watch?v=tFUi8Wa03hc