B

Bob Axsom

Well Known Member
Here are the RV-8 and RV-8A racing speeds extracted from www.sportairrace.org (RV Red = 320, RV Blue = 360, RV Gold = 390):

Race Record (RR)# Race Date Class Aircraft Type Pilot Speed Kts Speed MPH
209 AirVenture Cup 2008 7/27/08 RV Blue RV-8 Huft, John 217.17 249.91
776 Rocket 100, 2010 11/20/10 RV Blue RV-8 Huft, John 205.39 236.36
47 AirVenture Cup 2007 7/23/07 RV Blue RV-8 Huft, John 204.56 235.40
213 AirVenture Cup 2008 7/27/08 RV Blue RV-8 Ross, Jon 202.59 233.14
1119 Tennessee Valley Air Race IV 10/29/11 RV Gold RV-8 Ring, Damon 202.23 232.72
632 AirVenture Cup 2010 7/26/10 RV Blue RV-8 Huft, John 201.97 232.42
446 Grace Flight 2009 10/4/09 RV Blue RV-8 Huft, John 201.71 232.12
1041 Tennessee 150 (Tullahoma) 9/10/11 RV Gold RV-8 Ring, Damon 201.57 231.96
309 Taylor 100 2009 3/16/09 RV Blue RV-8 Huft, John 201.29 231.64
214 AirVenture Cup 2008 7/27/08 RV Gold RV-8 Martin, Dick 202.28 231.63
691 Pagosa Springs 2010 9/26/10 RV Blue RV-8 Huft, John 200.93 231.07
176 Colorado 150, 2008 6/29/08 RV Blue RV-8 Huft, John 199.27 229.31
429 Pagosa Springs 100 2009 9/27/09 RV Blue RV-8 Huft, John 199.38 229.29
296 Rocket 100 2008 11/23/08 RV Blue RV-8 Huft, John 197.43 227.20
515 Texoma 100 4/25/10 RV Gold RV-8 Ogden, Deene 197.15 226.72
778 Rocket 100, 2010 11/20/10 RV Gold RV-8 Ogden, Deene 196.89 226.58
1082 Northwoods 100 10/8/11 RV Gold RV-8 Ring, Damon 196.34 225.94
899 Memorial 130, Terrell, TX 5/28/11 RV Gold RV-8 Hajek, Jerry 196.00 225.55
873 Lone Star Air Rally 5/14/11 RV Gold RV-8 Hajek, Jerry 195.77 225.29
779 Rocket 100, 2010 11/20/10 RV Blue RV-8 Rovey, Jason 195.44 224.90
1092 Cleveland Texas Air Race 10/15/11 RV Gold RV-8 Hajek, Jerry 195.29 224.73
116 Rocket 100, 2007 11/18/07 RV Blue RV-8 Huft, John 194.78 224.15
586 Sulphur Springs 130 7/18/10 RV Gold RV-8 Ogden, Deene 194.59 223.94
780 Rocket 100, 2010 11/20/10 RV Gold RV-8 Hajek, Jerry 194.43 223.74
50 AirVenture Cup 2007 7/23/07 RV Gold RV-8 Martin, Dick 194.36 223.67
1120 Tennessee Valley Air Race IV 10/29/11 RV Gold RV-8 Hajek, Jerry 193.99 223.24
218 AirVenture Cup 2008 7/27/08 RV Blue RV-8 Carroll, Alan 193.76 222.97
749 Tennessee Valley Air Race 2010 10/30/10 RV Blue RV-8 Rovey, Jason 193.50 222.72
900 Memorial 130, Terrell, TX 5/28/11 RV Blue RV-8 Rovey, Jason 193.53 222.72
132 Texoma 100, 2008 4/20/08 RV Blue RV-8 Christman, Dave 192.88 222.00
750 Tennessee Valley Air Race 2010 10/30/10 RV Blue RV-8 Carroll, Alan 192.07 221.07
833 Texoma 100, 2011 4/16/11 RV Gold RV-8 Hajek, Jerry 192.17 221.07
55 AirVenture Cup 2007 7/23/07 RV Blue RV-8 Ross, Jon 192.04 221.00
56 AirVenture Cup 2007 7/23/07 RV Blue RV-8 Carroll, Alan 191.77 220.68
966 Big Sky Air Race 7/9/11 RV Blue RV-8 Rovey, Jason 191.31 220.15
1022 Indy Air Race 8/13/11 RV Blue RV-8 Carroll, Alan 191.29 220.14
1074 Thunderbird 150 10/8/11 RV Blue RV-8 Rovey, Jason 191.23 220.06
1075 Thunderbird 150 10/8/11 RV Blue RV-8 Taylor, Craig 190.85 219.62
901 Memorial 130, Terrell, TX 5/28/11 RV Gold RV-8A Sutterfield, Stan 190.82 219.59
946 2011 West Tesas 100 6/18/11 RV Blue RV-8 Rovey, Jason 190.36 219.07
1007 AirVenture Cup (TH) 2011 7/25/11 RV Gold RV-8 Ring, R. Damon 190.31 219.00
399 AirVenture Cup 2009 7/27/09 RV Blue RV-8 Huft, John 189.13 217.69
636 AirVenture Cup 2010 7/26/10 RV Blue RV-8 Ross, Jon 189.01 217.51
311 Taylor 100 2009 3/16/09 RV Blue RV-8 Carroll, Alan 188.96 217.46
664 Great Canadian Air Rally 2010 8/22/10 RV Blue RV-8 Carroll, Alan 188.83 217.30
834 Texoma 100, 2011 4/16/11 RV Gold RV-8A Sutterfield, Stan 188.88 217.28
497 Taylor 150 4/11/10 RV Gold RV-8 Ogden, Deene 188.69 217.14
1143 Rocket 100, 2011 11/19/11 RV Blue RV-8 Rovey, Jason 188.43 216.84
312 Taylor 100 2009 3/16/09 RV Blue RV-8 Christman, Dave 188.33 216.73
588 Sulphur Springs 130 7/18/10 RV Blue RV-8 Rovey, Jason 188.12 216.48
537 West Texas 100 6/6/10 RV Blue RV-8 Huft, John 187.99 216.33
223 AirVenture Cup 2008 7/27/08 RV Blue RV-8 Schryver, Fred 187.49 215.76
785 Rocket 100, 2010 11/20/10 RV Blue RV-8 Grover, David 187.39 215.65
836 Texoma 100, 2011 4/16/11 RV Blue RV-8 Taylor, Craig 186.87 214.97
1057 Pagosa Springs 100 9/24/11 RV Gold RV-8 Hajek, Jerry 186.56 214.69
695 Pagosa Springs 2010 9/26/10 RV Blue RV-8 Rovey, Jason 186.47 214.45
904 Memorial 130, Terrell, TX 5/28/11 RV Blue RV-8 Taylor, Craig 186.31 214.41
1000 AirVenture Cup (Matoon) 2011 7/24/11 RV Gold RV-8 Ring, R. Damon 186.05 214.11
715 Grace Flight 2010 10/2/10 RV Blue RV-8 Carroll, Alan 185.70 213.69
716 Grace Flight 2010 10/2/10 RV Blue RV-8 Rovey, Jason 185.32 213.25
717 Grace Flight 2010 10/2/10 RV Blue RV-8 Christman, Dave 184.94 212.81
718 Grace Flight 2010 10/2/10 RV Gold RV-8 Ogden, Deene 184.86 212.73
59 AirVenture Cup 2007 7/23/07 RV Blue RV-8 Jordan, Scott 184.85 212.72
60 AirVenture Cup 2007 7/23/07 RV Blue RV-8 Schryver, Fred 184.85 212.72
1059 Pagosa Springs 100 9/24/11 RV Blue RV-8 Rovey, Jason 184.39 212.19
696 Pagosa Springs 2010 9/26/10 RV Blue RV-8 Taylor, Craig 183.31 210.81
638 AirVenture Cup 2010 7/26/10 RV Blue RV-8 Carroll, Alan 182.98 210.57
178 Colorado 150, 2008 6/29/08 RV Blue RV-8 Carroll, Alan 181.34 208.68
1148 Rocket 100, 2011 11/19/11 RV Blue RV-8 Krebaum, Ken 180.72 207.97
947 2011 West Tesas 100 6/18/11 RV Blue RV-8 Krebaum, Ken 180.69 207.93
337 Texoma 100 2009 5/31/09 RV Blue RV-8 Tuckey, Pat* 180.59 207.82
404 AirVenture Cup 2009 7/27/09 RV Gold RV-8 Martin, Dick 180.44 207.65
405 AirVenture Cup 2009 7/27/09 RV Blue RV-8 Ross, Jon 180.44 207.65
538 West Texas 100 6/6/10 RV Blue RV-8 Rovey, Jason 179.91 207.04
1060 Pagosa Springs 100 9/24/11 RV Blue RV-8 Taylor, Craig 179.81 206.92
787 Rocket 100, 2010 11/20/10 RV Blue RV-8 Hopkins, Dan 179.74 206.84
434 Pagosa Springs 100 2009 9/27/09 RV Blue RV-8 McCann, Jim 179.42 206.33
972 Big Sky Air Race 7/9/11 RV Blue RV-8 Malott, Paul 179.11 206.12
841 Texoma 100, 2011 4/16/11 RV Blue RV-8 Krebaum, Ken 178.69 205.55
790 Rocket 100, 2010 11/20/10 RV Red RV-8 Jones, Bryan 177.27 204.00
697 Pagosa Springs 2010 9/26/10 RV Blue RV-8A Crossley, Eber 177.21 203.79
407 AirVenture Cup 2009 7/27/09 RV Blue RV-8 Carroll, Alan 176.87 203.54
905 Memorial 130, Terrell, TX 5/28/11 RV Blue RV-8 Krebaum, Ken 176.41 203.01
570 Top of the Chesapeake 7/11/10 RV Blue RV-8 Robertson, Gordon 176.38 202.97
863 BCAF 2011 4/30/11 RV Gold RV-8 Hajek, Jerry 175.16 201.57
816 Taylor 150, 2011 4/2/11 RV Blue RV-8 Holladay, Chad 174.21 200.48
700 Pagosa Springs 2010 9/26/10 RV Blue RV-8 Greenberg, Redge 173.42 199.43
525 Texoma 100 4/25/10 RV Blue RV-8 Stanton, Danny 173.10 199.07
280 Memphis 100 2008 10/19/08 RV Blue RV-8A Labarreare, Chuck 172.70 198.74
1098 Cleveland Texas Air Race 10/15/11 RV Red RV-8 Jones, Bryan 171.33 197.16
16 Taylor 100 2007 5/20/07 RV Red RV-8 Jones, Bryan 169.45 195.00
820 Taylor 150, 2011 4/2/11 RV Gold RV-8 Hajek, Jerry 161.20 185.51
1068 Pagosa Springs 100 9/24/11 RV Blue RV-8A Crossley, Eber 158.79 182.73
506 Taylor 150 4/11/10 RV Blue RV-8 Hopkins, Dan 156.48 180.07
1107 Cleveland Texas Air Race 10/15/11 RV Blue RV-8 Hopmann, Bo 156.00 179.52
1158 Rocket 100, 2011 11/19/11 RV Blue RV-8 Hopmann, Bo 152 174.92

Note: because of rule changes and pilot desire for more challenge some class names are changed here to reflect the engine used in the airplanes - Dick Martn flew in Sport FX before there was an RV Gold Class and John Huft just wanted to take on the 390s with his 360.

Bob Axsom
 
Well ... no average really

Those are the actual speeds to cover the various courses (ground speeds may be higher but in the wrong - off course - direction). The winds and altitudes are peculiar to each leg and there are often hard turns involved (except for the AirVenture Cup on even numbered years - straight east bound shot from Mitchell, SD to Oshkosh). There are no calculations involved. The legs are not equal and opposite and careful altitude planning can allow a racer to exceed the top speed of his airplane by playing the winds. I think your idea is correct but I don't want to mislead anyone (too late for that I guess).

Bob Axsom
 
Last edited:
What Bob is trying to say is these speeds are utterly useless as a comparison to anyone's RV-8. They're not true airspeed, and technically they are not groundspeed.
 
DanH said:
What Bob is trying to say is these speeds are utterly useless as a comparison to anyone's RV-8. They're not true airspeed, and technically they are not groundspeed.
Click to expand...

Its true these speeds are not directly comparable to the speed measured for anyone's RV-8, but they're not entirely useless. The SARL has generated a huge amount of primary data by careful timing of airplanes that generally are pushing to fly as fast as possible. Bob's master spreadsheet has something like 1000 entries all told! Individual data points are influenced by winds, course configuration, pilot skill and decisions, etc. However, in aggregate these variations tend to be averaged out in a way that allows objective comparison between different aircraft types. See this thread for example:

http://www.vansairforce.com/community/showthread.php?t=68019&highlight=race

Of course if you really want to find out how your airplane compares to others the thing to do is enter a race (which also happens to be a lot of fun)!:

http://www.sportairrace.org/
 
Last edited:
DanH said:
..... these speeds are utterly useless as a comparison.....
Click to expand...

Well not utterly useless. When other people who have raced, look at these lists Bob has compiled, you can see some planes are faster than others under race conditions. Some peoples had their RV's tuned to kick butt....true airspeed or ground speed, and it shows in these lists.

If a person wanted to compare their RV-8 just try to duplicate some of these speeds by running your own XC(straight line or closed course). You can see where you fall in line. OR you could go to a SARL event and actually see what you and your equipment is capable of.

BTW- in RV-8's I'd put my money on John Huft. In RV-6's my wager will be Bob A.
 
hydroguy2 said:
Well not utterly useless. When other people who have raced, look at these lists Bob has compiled, you can see some planes are faster than others under race conditions. Some peoples had their RV's tuned to kick butt....true airspeed or ground speed, and it shows in these lists.

If a person wanted to compare their RV-8 just try to duplicate some of these speeds by running your own XC(straight line or closed course). You can see where you fall in line. OR you could go to a SARL event and actually see what you and your equipment is capable of.

BTW- in RV-8's I'd put my money on John Huft. In RV-6's my wager will be Bob A.
Click to expand...

Only if all racers flew the same profile (altitudes, turn points, etc...)


I believe the definition of AVERAGE ground speed would be the total distance from start to finish divided by the total time start to finish, which would account for all turns, climbs, course deviations, winds, etc...

I'll assume the speeds you posted are calculated this way.
 
If we assume zero wind and constant altitude, the actual true airspeeds for a closed course are probably higher than the reported figures.

I say probably because I'm guessing the course distance used for calculation is pylon to pylon and doesn't include the extra distance necessary to turn round a pylon.
 
DanH said:
If we assume zero wind and constant altitude, the actual true airspeeds for a closed course are probably higher than the reported figures.

I say probably because I'm guessing the course distance used for calculation is pylon to pylon and doesn't include the extra distance necessary to turn round a pylon.
Click to expand...

agree. Which is exactly the reason these numbers are of little value for comparison from plane-to-plane as no two racers flew the same distance under the same conditions.
 
I think everyone knows basically what is going on here

I think everyone knows basically what is going on here so I will not try to change anyone's mind but there are a couple of points to clear up.

Turns - there is a unique turn distance included in the course length for all turns in all races. I'm just a racer when I can and a record keeper because I think competitive speed records are important to keep. I don't know what radius is used to determine the turn distance but a race organizer once used the wrong distance - too generous - and when the speeds were redetermined I had to do a lot of work updating and resorting the records & statistics tables.

Racing speeds - Granted the first few times you race you climb into your airplane fly the course at a safe altitude and hope to catch a tail wind that no one else is lucky enough to catch and your race speed will be near or less than your true airspeed. However, wind planning alone can usually give you a race speed that is faster than your true airspeed. On races of 100-150 miles with 5 or 6 turns the altitude range is usually no more than 3000 feet but in that range the ground speed can always be changed by altitude selection alone sometimes by many knots. It is the last thing I finalize in my race preparation - the altitude I will fly each leg - the night before the race based on the forecast for the time of the race. The next morning I recheck the forecast but they usually hold very well over that short span - if not I have everything in an Excel spread and I input the necessary changes and fly the new plan.

Bob Axsom
 
DanH said:
If we assume zero wind and constant altitude, the actual true airspeeds for a closed course are probably higher than the reported figures.

I say probably because I'm guessing the course distance used for calculation is pylon to pylon and doesn't include the extra distance necessary to turn round a pylon.
Click to expand...

Actually the distance is based on pylon to pylon PLUS the turn distance is added, based on 180kt and 2G turn. I don't recall the actual numbers but for the BigSkyAirRace there was an addition 3 or 4 miles added to the ~130nm course due to the number and total degrees of turns.
 
It is hard to know how to react to a comment like
utterly useless as a comparison
Click to expand...
other then to point out that passing someone, or being passed by someone is pretty definitive. Yes winds and turns have an effect on the final speed but when you see the guy in front of you pull away you know that he is faster and it has nothing to do with wind, turns or pilot skill, the plane is simply faster, end of story. The data clearly shows that there is a big difference in the speed of different aircraft in the same class.
It is a sharing group, and many have benefitted from what the faster guys have learned; I have added 40 mph to my aircraft since the first time I participated in these races. But what does this have to do with every day flying?
On the trip home from Texas this year I used two gallons per hour LESS fuel then Jim Winnings flying at the same cross country airspeeds. This was not the case when I first started flying this particular airplane. Ask Jim, he is amazed at how much more efficient my aircraft is.
It will make more sense after you have joined in and participated.
 
But I cannot use the RV Blue speed numbers as a comparison to my RV8 and determine some relative level of efficiency because those race speeds are not an apples-apples comparison to True or Indicated Airspeed as a function of Power and Fuel Flow -

Efficiency is a tricky word and needs specific definition in every case.

Certainly some planes are faster than others but by how much and under what conditions? If racer A was able to turn inside the standard radius and take better advantage of winds than racer B it is feasible Racer B has a faster plane but the speed reported may show racer A as faster. Also some of you guys are running way above 2700rpm right?

My initial question was merely to understand the data as presented

Anyway not trying to start a fight..just want to understand the info.
 
The only way you are ever going to have a "valid" comparison of your aircraft to another aircraft is to fly side by side. There are simply too many variables in instrumentation and weather conditions to do it any other way. Racing the same day with another plane of the same type certainly lets you know how you stack up. I think the data is awesome as a tool when you consider the total absence of anything else.
 
Thanks

Bob Axsom said:
I think everyone knows basically what is going on here so I will not try to change anyone's mind but there are a couple of points to clear up.
Bob Axsom
Click to expand...

Bob,
I would like to thank you for all the work you put into extracting this data. I do find it useful, and it is interesting to see results from past races. It is always a good thing to have a record to look back on. By looking at the race records, you can tell if someone flew a good race, a bad race, had difficulty( got lost or maybe ran part of the race backwards !) pay no attention to those who discount what you have done, many of us respect the work, and time you have put into it..

Thank You
 
Tom Martin said:
The only way you are ever going to have a "valid" comparison of your aircraft to another aircraft is to fly side by side. There are simply too many variables in instrumentation and weather conditions to do it any other way.
Click to expand...

This is certainly true. Its very hard to know what to make of self-reported speeds because they almost never include complete documentation of the conditions and procedures under which they were obtained. On the other hand there's an undeniable reality in seeing someone else pass you during a race (or in passing them)!
 
C-FAH Q said:
Bob,
pay no attention to those who discount what you have done, many of us respect the work, and time you have put into it..

Thank You
Click to expand...

Relax, nobody is discounting anyone. Just looking for clarification of data so I may find some usefulness in it...

The most useful of which is that John Huft would be the guy to talk to about RV8 speed mods. All other data is qualitative in nature...
 
I can't speak for anyone but myself, but I run my IO-360 at 2500-2570rpm and ~100*ROP. I figure this gives me a balance of good power and longevity.

I also think these results are actually more realistic numbers than those obtained from the perfect 4way GPS box run. Lots of work to get the same conditions each time. Whereas, running a course, whether it is in a race or one you lay out yourself is real world conditions. Are there variable conditions? sure.

I have a LongEz guy around here who got a new prop and said he gained 15mph w/ a top speed of 215mph and was going to show those RV's the back end of a canard. I thought "wow" that's pretty good for a 0-320, I'm hoping I can run 215mph course speed, but then came race day. I don't know for sure what power settings he ran but he only averaged 181mph and even cut inside of 2 corners. So much for bragging about what your plane can do, I beat him on the same course the same day by 30mph! I understand these are different planes, different engines, etc...but he was the one running his mouth.

If you look at the numbers Bob has gathered, you can find who races a lot and also who has only entered 1 or 2. I tried to compare my initial testing numbers against SARL speeds to see where I might fit in the mix. I thought I would be above average and turns out that's about where I am. I also try to find comparable planes that are equipped similarly. No sense trying to measure up against a RV-8 angle valved IO-360 with 10 to 1 pistons turning a race prop at 3000rpm. But I do compare myself against the numbers of RV-6's and -7's running parallel valve 360's and any prop/rpm combo. Then I just try to improve my own numbers, either by technique or modifications to the airframe. I felt I should run 180kts. 1st race I was 177kts, 2nd race again my goal was 180kts, but managed 184. A little of the improvement was engine management but mostly technique finding the turns and flying straight. Next season I hope to average 187kts.
 
Last edited:
You must log in or register to reply here.