X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imo-d04.mx.aol.com ([205.188.157.36] verified) by logan.com (CommuniGate Pro SMTP 5.0.8) with ESMTP id 970754 for flyrotary@lancaironline.net; Sun, 05 Feb 2006 02:06:15 -0500 Received-SPF: pass receiver=logan.com; client-ip=205.188.157.36; envelope-from=Lehanover@aol.com Received: from Lehanover@aol.com by imo-d04.mx.aol.com (mail_out_v38_r6.3.) id q.218.12861421 (62952) for ; Sun, 5 Feb 2006 01:58:57 -0500 (EST) From: Lehanover@aol.com Message-ID: <218.12861421.3116fc31@aol.com> Date: Sun, 5 Feb 2006 01:58:57 EST Subject: Re: [FlyRotary] Re: Suitability of NPG for Rotary Engine use To: flyrotary@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1139122737" X-Mailer: 9.0 SE for Windows sub 5022 X-Spam-Flag: NO -------------------------------1139122737 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 2/4/2006 10:53:43 PM Eastern Standard Time, ceengland@bellsouth.net writes: I remember some report of a race team (NASCAR, I think) going for a speed record on a banked closed course. Report was that the car, which was supposedly very successful in races, overheated fairly quickly when run flat out. Supposedly, the off-throttle time during racing is very significant in reducing total heat load of the engine. Again, supposedly, no such luxury is available in a/c. Is there any validity in the story or concepts presented? Airfoil for 2400lbs @200mph: How about, find someone building an RV-10 & copy that? Charlie It is possible if it was a short track setup being done as a lark. The superspeedway cars are flat out at close to 100% duty cycle. Slowing only for danger or pit stops. Typical revs around 7,800 to 8,000 RPM. Short track engines are run over 9,000 RPM. But short tracks require quite a bit of off throttle time. They also think things like 260 oil temps and 240 water temps are OK. As the new driver gets better, the cooling gets worse. Because you are not cutting down lap times with both feet on the brake pedal. Learning the limit of adhesion in all situations is the drivers job. Hopefully learning it all in one chassis. My friend Joe Salyer (1960 Bonanza with a 550) entered his Chevron (290HP 1,500 pounds) in a CanAm race at Mid Ohio years back. In practice he went as deep as he thought he could into the braking area at the end of the long back straight. While he was on the brakes as hard as possible, his mirrors turned red and Allen Jones ( X formula one driver) in a bright red Chevy powered Lola rocketed by still at top speed, whipped in front of Joe, waved a thanks (for not pulling in front of him) dynamited the brakes and vanished around the tight right hander. Joe determined that there was more braking power available than he was using. The long spooldown braking period seen in the novice lap, is all but missing in the pro lap. And so then, is the long, off throttle period that reduces the heat load on the radiator. As off throttle time goes down, duty cycle closes in on 100% and the true cooling capacity of the system becomes apparent. While racing can pinpoint a fault in a power system by overstressing it. Racing cannot duplicate the duty cycle of the aircraft installation. The more modern teams NASCAR, now lease engines from just a few engine builders. The development dynos are running constantly, and the computers can and do replicate an entire race at any track they choose, including a blocked radiator opening, overheated coolant and oil, and every pit stop. You seldom see one drop out from just engine problems. The aircraft installation has a total stress level that is a bit lower than racing, but the support systems are loaded at a higher level on a time basis. So it is the support systems that need the work. In general, the engine will be fine at any output level. Lynn E. Hanover -------------------------------1139122737 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
In a message dated 2/4/2006 10:53:43 PM Eastern Standard Time,=20 ceengland@bellsouth.net writes:
<= FONT=20 style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size= =3D2>I=20 remember some report of a race team (NASCAR, I think) going for a
spee= d=20 record on a banked closed course. Report was that the car, which
was=20 supposedly very successful in races, overheated fairly quickly when
ru= n=20 flat out. Supposedly, the off-throttle time during racing is very=20
significant in reducing total heat load of the engine. Again,=20
supposedly, no such luxury is available in a/c. Is there any validity=20= in=20
the story or concepts presented?

Airfoil for 2400lbs @200mph: H= ow=20 about, find someone building an RV-10 &
copy=20 that?

Charlie
 
It is possible if it was a short track setup being done as a lark. The=20 superspeedway cars are flat out at close to 100% duty cycle. Slowing only fo= r=20 danger or pit stops. Typical revs around 7,800 to 8,000 RPM. Short track eng= ines=20 are run over 9,000 RPM. But short tracks require quite a bit of off throttle= =20 time. They also think things like 260 oil temps and 240 water temps are=20 OK.
 
As the new driver gets better, the cooling gets worse. Because you are=20= not=20 cutting down lap times with both feet on the brake pedal. Learning the limit= of=20 adhesion in all situations is the drivers job. Hopefully learning it all in=20= one=20 chassis.
 
My friend Joe Salyer (1960 Bonanza with a 550) entered his Chevron (290= HP=20 1,500 pounds) in a CanAm race at Mid Ohio years back. In practice he went as= =20 deep as he thought he could into the braking area at the end of the long bac= k=20 straight. While he was on the brakes as hard as possible, his mirrors turned= red=20 and Allen Jones ( X formula one driver) in a bright red Chevy powered Lola=20 rocketed by still at top speed, whipped in front of Joe, waved a thanks (for= not=20 pulling in front of him) dynamited the brakes and vanished around the tight=20 right hander.
 
Joe determined that there was more braking power available than he was=20 using.
 
The long spooldown braking period seen in the novice lap, is all but=20 missing in the pro lap.
And so then, is the long, off throttle period that reduces the heat loa= d on=20 the radiator. As off throttle time goes down, duty cycle closes in on 100% a= nd=20 the true cooling capacity of the system becomes apparent.
 
While racing can pinpoint a fault in a power system by overstressing it= .=20 Racing cannot duplicate the duty cycle of the aircraft installation.
 
The more modern teams NASCAR, now lease engines from just a few engine=20 builders.
The development dynos are running constantly, and the computers can and= do=20 replicate an entire race at any track they choose, including a blocked radia= tor=20 opening, overheated coolant and oil, and every pit stop.
 
You seldom see one drop out from just engine problems.
 
The aircraft installation has a total stress level that is a bit lower=20= than=20 racing, but the support systems are loaded at a higher level on a time basis= . So=20 it is the support systems that need the work. In general, the engine will be= =20 fine at any output level.
 
Lynn E. Hanover
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