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rv6ejguy
03-05-2008, 01:43 PM
We're planning a short cross country race here and wanted to plan intervals for the aircraft. What sort of speeds are you Rocket drivers seeing at say 6-8000 feet?

mark manda
03-05-2008, 02:28 PM
http://img341.imageshack.us/img341/57/2508017nk3wi4.jpg (http://imageshack.us)


http://img341.imageshack.us/img341/9672/89253062clugg4luxy6vl0.jpg (http://imageshack.us)


mine's slower than most.

Kahuna
03-06-2008, 03:49 AM
We're planning a short cross country race here and wanted to plan intervals for the aircraft. What sort of speeds are you Rocket drivers seeing at say 6-8000 feet?

Mine is not a rocket. Buts its ball park. You could ad ~5kts to get a rocket speed. Course I have out run a couple in head to heads. But Im giving em 5kts on the shorter wing to make em feel better. Im sorry, was I bragging?:)
You can find lots of performance data here.
http://mstewart.net/super8/performance/propcomparisons.htm

Best,

Linedog
03-06-2008, 09:15 AM
Are you talking "normal" cross country speeds, or race speeds? It depends on how much gas you want to burn! If guys want to go fast, they may well use different altitudes. It may also depend on whether it is an EVO or Sport wing, as they are optimized for different altitudes...and of course depends on race length.

We had a 100 mile "navigation exercise" down here in Memphis with 6 Rockets. Everyone stayed low, and the speeds were generally in the 210-220 Kt range for the whole course.

For a sport wing a wag round race number in the 6-8K' range would be 210-215 KTAS? For an EVO maybe 215-220 KTAS?

Hope this helps...

rv6ejguy
03-06-2008, 10:18 AM
Yep, race speeds. So 200-220 knots in in the normal range. Thanks. This will help in planning.

f1rocket
03-06-2008, 11:35 AM
Mine is not a rocket. Buts its ball park. You could ad ~5kts to get a rocket speed. Course I have out run a couple in head to heads. But Im giving em 5kts on the shorter wing to make em feel better. Im sorry, was I bragging?:)
You can find lots of performance data here.
http://mstewart.net/super8/performance/propcomparisons.htm

Best,

Man it is time to put this BS to bed!:D

We've all flown with the Indy Super-8s and unless you found some super secret speed mod, I'm pretty sure 5 knots is quite conservative. Of course, we're never going to know for sure until we get in a side-by-side comparison.;)

Linedog
03-06-2008, 11:49 AM
Randy...

Anybody that has to brag to get listened to...well...isn't worth paying attention to? He didn't show at our race... It would have been the perfect opportunity to prove his "speed".

On the other hand, I was surprised at how fast a buddies new RV-8 is. Without wheel pants he was getting 170 kts out of a IO-390..so that just might put him within 15 knots of the Rockets!

Jeff

f1rocket
03-06-2008, 02:38 PM
Hey Jeff,

We kid Kahuna all the time. He does have a very nice Super 8 and he's a good guy too. He's been up to Indy a couple of times to consult with the Super 8 guys but I can never seem to hook up with him.:rolleyes:

Come to think of it, I remember we extended him an invitation to the Memphis race but his email was suddenly silent. Must have been a temporary equipment failure.

Kahuna
03-06-2008, 10:05 PM
All of my performance data has been posted for all to see and nit pick.
My best ever seen on the efis straight and level was 206KTAS. That

Im just messin with you rocket guys. You are faster. I conceed. Clearly my longer wings bust me out on the running.

I do like the head to heads though, especially against the 3 blade fellas.

Dont get your panties in a waad when I pick at ya. The rockets are awesome, and indeed faster. The only 2 I have run against both had 3 blades. Both were out run by a knot or 2. You can see by my 3 blade data that it is a distinct disadvantage.

Best,

Tom Martin
03-07-2008, 05:39 AM
The beauty of racing is that it really sorts out the men and their machines. The sport aircraft racing league is open to all competitors, there are no fees, few awards, but lots of fun. http://sportairrace.org/index.html Real life rockets speeds are posted in the race results. The fastest RV8, owned by John Huft is very close to the slowest rockets and about 20mph off the faster rockets. He does this with an exceptionally clean FOUR cylinder RV8. Power is not everything as attention to detail can make huge differences. Mike Stewart, with a 540 should be in the same range as the rockets, I would be surprised if he was not. Races let you see how you and your airplane compare to others. Rocket race speeds in the 200 to 215 knot range are going to catch 99% of the planes.

f1rocket
03-07-2008, 08:55 AM
All of my performance data has been posted for all to see and nit pick.
My best ever seen on the efis straight and level was 206KTAS. That

Im just messin with you rocket guys. You are faster. I conceed. Clearly my longer wings bust me out on the running.

I do like the head to heads though, especially against the 3 blade fellas.

Dont get your panties in a waad when I pick at ya. The rockets are awesome, and indeed faster. The only 2 I have run against both had 3 blades. Both were out run by a knot or 2. You can see by my 3 blade data that it is a distinct disadvantage.

Best,

Oh, I get it. I just like pulling your chain too. To me, it's all good. I love most every airplane.

While a race would tell the tale, it would also eliminate the fun of the mystery. It's kind of like once you found out who Deep Throat was, it wasn't fun anymore!

Dayton Murdock
03-07-2008, 09:15 AM
Hi Tom
When the sport races are ran what altitude do they run at? are the speeds recorded from a standing start over the distance,or is it a running start?

Linedog
03-07-2008, 09:21 AM
To the Big Kahuna...I apologize if it sounded like I had my dander up... ya know..sometimes it is hard to "read" e-mails... and bragging and playful banter is sometimes hard to discern...?! :o

Anyways, hope that we can get all the Indy and MEM guys together soon for some fun. ...and Kahuna, I'll even "give you a couple" if it'll help your ego!?! :D

After seeing my buddies IO-390 RV-8 haul, I gotta tell ya, it made me think about the Rocket lite that Mark has been talking about... He may really be on to something! To fly rocket speeds with less burn!? Cool!

f1rocket
03-07-2008, 10:28 AM
Hi Tom
When the sport races are ran what altitude do they run at? are the speeds recorded from a standing start over the distance,or is it a running start?

I timed the Taylor race this past fall. The altitude is pilot choice, but most are as low as they can safely fly. It is a flying start over a fixed point.

Mel
03-07-2008, 10:50 AM
Note that most "Rockets" have a maximum cruise CAS of less than 180 knots as shown by their 3" N numbers.

f1rocket
03-07-2008, 11:56 AM
That's correct. Calibrated Air Speed, as shown on the airspeed indicator at 10,000 feet MSL, is about 160 KTS.

The regs call out 180KT CAS at cruise. The manufacturer of the kit stipulates a cruise of 230MPH TAS at 10,000MSL, which is 200KT TAS.

As you recall from flight school, TAS diverges from IAS at about 2% per thousand feet of altitude, so the IAS at cruise (200KT TAS) would be 20% less, or 160KT. Now, if you happened to calibrate your ASI, you would indicate 160KT at cruise, well under the 180KT CAS limit.

Cruise is a manufacturers' spec, and the manufacturer can call out the altitude and power settings for this condition.

Tom Martin
03-07-2008, 05:58 PM
Dayton
Individual pilots are responsible to follow the rules of the airspace in regards to altitude. That being said most races are held in areas that are sparsely populated so altitude is one of the pilot choices. Generally, if the air is calm, there is more power available down low. However you really do have to take into account the upper winds around the course. In the rocket 100 race I was all the way from real low to 3000 agl on two different legs. It is easy to just bomb around at a fixed altitude but with a little research and a bit of luck you just might catch a tail wind up high that more than compensates for less manifold pressure.

Bob Axsom
03-08-2008, 08:21 AM
Hi Tom
When the sport races are ran what altitude do they run at? are the speeds recorded from a standing start over the distance,or is it a running start?

The minimum altitude depends on the race and what is coordinated with the FAA. In the AirVenture Cup Race several special "floors" were required by the FAA at specific locations otherwise the minimum altitude is the same as for every other pilot flying in the airspace. The speeds are recorded from some specific point with inbound limitations to prevent diving at the start time line. In the AirVenture Cup Race the time starts at the departure end of the runway. In the Taylor Texas race it is just to the west of the Hutto water tower several miles from the airport. In the Memphis 100 it was at the intersection of a railroad track and a road several miles from the airport. The fastest plane takes off first and is followed by the rest of the planes in declining speed order at approximately 30 second intervals (traffic permitting). It is rare to see another racer after takeoff as the space continues to increase. In the Memphis 100 last year everyone that expected the possibility of exceeding 250 kts had to sign a waiver (No I didn't have to sign darn it). There are no standing start races in the SARL events (www.sportairrace.org). The actual complete set of rules including the start and altitude floors for this year's Taylor 125 are currently posted at the SARL site for you to study if you like. Click on Calendar of events then the underlined text in the Taylor 125 posting. From there you can see the photos of the turn points, the current list of entries, etc.

Bob Axsom, Race #71

smokyray
03-19-2008, 09:41 AM
The real question though, can you shoehorn your speedster into my 1800' strip for a cold beverage? :)
Fights on!

Smokey
HR2

1V1 spoken here...much more fun than racing!

http://img377.imageshack.us/img377/9819/img0171lq3.th.jpg (http://img377.imageshack.us/my.php?image=img0171lq3.jpg)
slight tailwind at 11.5...