RE: Apc props and the Nelson LS Q40 motor  
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RE: Apc props and the Nelson LS Q40 motor - 2/27/2007 6:12:44 PM   
HighPlains


 

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Joined: 3/2/2003
From: Over da rainbow, KS, USA
Status: offline 		Pollyanna rules!

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(in reply to diggs_74)
       Post #: 26

RE: Apc props and the Nelson LS Q40 motor - 2/27/2007 7:02:45 PM   
luv to race


 

Posts: 465
Joined: 12/10/2002
From: Liquored, FL,
Status: offline 		Here is something to chew on.

From a stand point of "failure analysis"... Any and All problems related to the prop issue are purely "speculation", and all reactions are from speculation. There is no test data (vibe test, flex test, harmonic freq tests, shock tests...) to prove anything at this point. Especially the airplane thing. To say that props broke on a particular type of aircraft is speculation, and that might of happened due to the larger quantity of that particular plane (who knows, right). I think everyone out there in Phx had a thought or opinion as to what the issues were. BUT... in the field of battle, reactions is all you have to go on. We were all just speculating as a group, searching for the answer.

What I do know is, as of Saturday Fred had thrown in the towel and said he wouldn't make anymore Q40 props. Which left us all scared out of our minds. Both options beyond Fred are brutal. Carve your own wood from blanks, or hand layed up full carbon... But there are 1/2 dozen guys to thank in helping Fred understand that we were not unhappy with him, and that we need him in our sport. So, I believe Fred has gone back to the shop.. in efforts of making a few new props.. possibly trying something shorter and/or thicker. Hopefully a month from now all issues will be under control.

The only thing I would of changed about the Phx race is. Once the 7.8's broke, like all other sizes did. I would of used that same inspection process and allowed the weaker pitched props back in the game (as most of you know, they inspected each planes prop as you got done with your heat). The only hard evidence that existed at that point was...all the props we fracturing. I think we broke more 7.6's because that's what guys were using. Only 2 or 3 guys were running the 7.8 before they deemed the 7.6 and 7.7 illegal. So odds were better prior to Saturday that 7.5's, 7.6's, and 7.7's were broke more
often.

RB

(in reply to HighPlains)
       Post #: 27

RE: Apc props and the Nelson LS Q40 motor - 2/27/2007 7:22:38 PM   
Bill Vargas



Posts: 1554
Joined: 1/6/2002
From: Team Coldies, CA, USA
Status: offline 		So now we can assume,,, that these 7.5, 7.6 and 7.7's will no longer be used anywhere because they were banned from PHX. ???

Any comments Barry?


BV

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(in reply to luv to race)
       Post #: 28

RE: Apc props and the Nelson LS Q40 motor - 2/27/2007 7:40:53 PM   
bl10


 

Posts: 303
Joined: 12/29/2001
From: Chatsworth, CA,
Status: offline 		Just waiting for AMA to weigh in this issue. They have the final say. I will follow their guide lines.


Barry

(in reply to Bill Vargas)
       Post #: 29

RE: Apc props and the Nelson LS Q40 motor - 2/27/2007 8:00:48 PM   
garys


 

Posts: 755
Joined: 1/31/2002
From: San Diego, CA, USA
Status: offline 		Bill, we can't assume anything. It's up to Fred and the AMA to decide if they'll continue to be legal.

This sport/hobby would not be where it is if it weren't for Fred. As Randy said, he was thinking of throwing in the towel with the carbon props, which would significantly hurt the event.

While it seemed like some airplanes may have had more issues than others, nearly every airplane design had at least one failure. I think it was a combination of several factors.

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GS

(in reply to bl10)
       Post #: 30

RE: Apc props and the Nelson LS Q40 motor - 2/27/2007 8:04:40 PM   
DHG


 

Posts: 896
Joined: 4/24/2002
From: Arvada, CO, USA
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quote:

ORIGINAL: djlyon

I mean geez, did somebody actually believe that the introduction of a new racing engine would happen without problems and a whole new set of unknowns?

To those of us old enough to remember Nelson's "shaker .15", this is all depressingly familiar. But it raises exactly the same question as 20 years ago: Why wasn't a 90% market share good enough? Why risk all this pain, upheaval, and expense for everybody involved -- most of whom were already your own customers anyway, and destined to stay that way -- just to drive out that last 10%?

Someone who competed in the event might ask that question.

(in reply to djlyon)
       Post #: 31

RE: Apc props and the Nelson LS Q40 motor - 2/27/2007 8:53:29 PM   
Bill Vargas



Posts: 1554
Joined: 1/6/2002
From: Team Coldies, CA, USA
Status: offline 		Thanks Barry for the answer. My reason for asking was for the up coming Basin Races.

GS, yes already spoke with Jim about those airframe issues,,, I am not worried about that and its a NON issue as far as I am concerned.

But I am sure, as I said before, an engine/prop fix will hopefully come about soon,,, other wise my Q40 days are over too.


BV

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If it ain't leaking oil, then something's wrong,,, USMC, RETIRED!

(in reply to DHG)
       Post #: 32

RE: Apc props and the Nelson LS Q40 motor - 2/27/2007 9:18:37 PM   
Yo! Team Green


 

Posts: 76
Joined: 3/25/2002
From: Rochester, WA, USA
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quote:

Based on this little bit of innuendo and lack of real information is it unreasonable to think of one nasty word, Coverup?


You cannot have the last word if you choose to make that word "Coverup". To answer your question.... Yes, it is unreasonable.

To even consider that the race organizers OR NMPRA officials would cover-up anything related to safety is ridiculous.

There are many factors to be investigated. Only a few have even been mentioned. We could sit out here in forum-land and make up a million. Personally, I'm pretty sure that the props broke when dust particles from the RC Car Nationals blew across the road and onto our race course. (That is how ridiculous this COULD get).

Jimmy did a great job of capturing data from PHX. Let the experts dig into it.

RB, I would think that eliminating the lower pitch props would reduce RPM, reduce tip speed, and lower cetripetal forces applied to the prop blades. That is why I thought they chose that route at PHX. And.. I sympathize with you.. the new motor that we were trying to run would not turn the 7.8 either - but we did not get it until Thursday so it did not have much time on it.
>Thom

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(in reply to diggs_74)
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RE: Apc props and the Nelson LS Q40 motor - 2/27/2007 9:44:57 PM   
garys


 

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Status: offline 		Duane, you've clearly had something against Henry for quite some time. I wouldn't say the new engine was because Henry is trying to increase his market share. For the last couple years, the Jett's have gotten faster. They clearly had the fastest airplanes at the Champ race in Medford. I would seriously be considering a move to Jetts if the Nelson's weren't improved. Let's not hang Mr. Nelson for making a faster moustrap, after all this is RACING, and the first one accross the finish line wins.

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GS

(in reply to Yo! Team Green)
       Post #: 34

RE: Apc props and the Nelson LS Q40 motor - 2/27/2007 10:48:42 PM   
daven



Posts: 6894
Joined: 12/7/2001
From: Andover, MN, USA
Status: offline 		Gary,

I completely agree with your last post. The past year plus has seen an increase in FAST Jett planes. Dubb/Mike/Jerry and the other Texans have always been fast, but lately there have been others. Gabriel has been wicked fast for the past two years, Brogdon had a plane at Witchita Falls last year that was a rocket also. Bruce had fast time at the Champ race in Houston last year, etc...

I was seriously considering trying a Jett motor for this year to try out, due to troubles I had been having with the newer (not LS) q40 motors. My last few, just weren't as good as some of my older motors. Close, but just not there, especially in hot / humid areas like Muncie.

I'm excited about the new motor, just hope we can get the prop issue settled or we have bigger issues.

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Dave Norman

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(in reply to garys)
       Post #: 35

RE: Apc props and the Nelson LS Q40 motor - 2/27/2007 11:09:28 PM   
DHG


 

Posts: 896
Joined: 4/24/2002
From: Arvada, CO, USA
Status: offline 		Gary, it's true, there's no love lost between me and Henry. But I don't begrudge the guy his right to make a living, nor do I question the quality or price of his product. What I do question is the sort of blitzkreig marketing we've just seen -- where everyone who's already made plans for the biggest race of the year suddenly has to either (a) double down their engine investment and spend a week doing hasty break-in and R&D, or (b) count on getting smoked. Because Henry's engines do go, there's no question about that. Even if there's no legal propeller made that can handle the horsepower, even if a bunch of guys quit and the event goes belly-up, he will make those engines sing. That he can do.


(in reply to garys)
       Post #: 36

RE: Apc props and the Nelson LS Q40 motor - 2/27/2007 11:56:12 PM   
garys


 

Posts: 755
Joined: 1/31/2002
From: San Diego, CA, USA
Status: offline 		I guess Henry could've done it like when the Jett BSE's showed up at the Nats and very few, if anybody, outside the Jett camp knew about them.

< Message edited by garys -- 2/28/2007 5:15:21 AM >

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GS

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RE: Apc props and the Nelson LS Q40 motor - 2/28/2007 1:37:47 AM   
bl10


 

Posts: 303
Joined: 12/29/2001
From: Chatsworth, CA,
Status: offline 		Duane:
The Jetts had a definite advantage at the end of the year. They not only won at Medford and Texas but set fast time by ¾ second over the best Nelson guys. So just exactly what would you expect Henry & Dave to do? No one had an inkling the props would be a problem. You certainly can’t blame Henry for something he has no control over. Between Scott, Mati, Lee and myself we put over 30 flights on the new engine with no prop failures. Others also flew the engine with no trouble. As far as people quitting I doubt anyone will quit that wasn’t already considering it. Most of us go through several planes and at least a couple of engines a year so I wouldn’t consider this an unusual expense. This is no more than normal racing evolution. There were 73 entries, the largest ever even larger than the Nats, at PHX and the vast majority of the Nelson guys had the new engines. If the event dies it won’t be because of new and better equipment. There are other forces at work that will make 40 size AMA pylon racing more and more difficult.

Anyone who doesn’t like the current rules can make a rules proposal to change it. Let’s see if we froze the engines at the end of last year we would all have to trash our Nelsons and buy Jetts, if we froze them now the Jett guys would be SOL. No one did anything under the table or against the rules.

Things always change in racing; it’s a fact of life.

Take Care
Barry

(in reply to garys)
       Post #: 38

RE: Apc props and the Nelson LS Q40 motor - 2/28/2007 2:40:51 AM   
Tony Pacini


 

Posts: 265
Joined: 1/11/2002
From: Prescott Valley, AZ, USA
Status: offline
quote:

ORIGINAL: Ed Smith

While on the subject of innuendo, there was a hint that certain airframes may have caused the prop problem. This was posted on the NMPRA site. If there was no hard evidence of this then it should not have been posted on any Forum. If there was hard evidence that certain airframes caused the prop problem then surely, in the interests of safety, the facts should be made public and the airframes named. Based on this little bit of innuendo and lack of real information is it unreasonable to think of one nasty word, Coverup?

Ed S


There are several factors to consider, many of which we probably don't even know about. Several items have been discussed because they seem more common than others.

All prop blade creases and/or failures that I heard of at the Phoenix race had one thing in common: the new engine. Some airframe types experienced more than one failure, some experienced no failures at all. Some pilots experienced multiple failures. There are many variables to consider.

Perhaps one single factor might not be responsible, but certain factors in combination with certain conditions may have contributed to the failures. Somebody will figure it out, but it won't be by discussing it on these forums.

The facts will be presented when they are known, and a solution will be offered. We just have to wait............



(in reply to Ed Smith)
       Post #: 39

RE: Apc props and the Nelson LS Q40 motor - 2/28/2007 4:20:15 PM   
DHG


 

Posts: 896
Joined: 4/24/2002
From: Arvada, CO, USA
Status: offline 		Barry,

I certainly don't blame Henry for the prop thing. It was inevitable that limit would be reached, and either Nelson or Jett would've been the first one to get there. But with virtually the entire field having already switched to the new engine, there was no Plan B. Now we're in a pickle, with Fred Burgdorf having to do a crash R&D program for new props, the AMA having to come up with emergency rules before the next contest, etc. It didn't have to be that way.

Gary,

Yes, incremental changes are made all the time. Last year's run of Nelsons was a notch above the previous version. I know; I have one. (Buy now! Limited-time offer! ) But I still say a major redesign with a 10% boost in horsepower and no interchangeable parts is a bit much to drop on people with one week's notice. What would've been wrong with releasing the new engine on Sunday afternoon at the contest? Same pre-contest publicity, same buzz, same number of sales to the same people, just less confusion and more opportunity to deal with any unforeseen problems like the propeller issue and the head spacing. It sure would've helped Barry and RB, as well as many others, I'm sure.

Kudos to Dave Shadel for offering as much help and advice as he could, but it wasn't fair to put him in that position either. He came to race, not to babysit.

Anyway, I should get off my soapbox. If I'm not paying entry fees, I have no right to complain. Good luck.

(in reply to bl10)