Ironflight

Ironflight

VAF Moderator / Line Boy
Mentor
Today I had to make a quick trip over to New Braunfels (TX) to visit the folks, and fortunately, it was a gorgeous day for flying. Weathermeister advised going out low and coming back high (normal for the winter), and boy, was it right on. The headwind at 4500? on the way out was actually much lower than I expected, so I continued the climb, only to see the headwind component go through the roof when I got above 5,000 ? so I headed back down and was satisfied to call it even. I like to get higher to save on fuel for the same TAS, but there?s no point in doing that if you?re going to lose it on time?

The return was one of those days to remember ? I climbed up to 9,500 for the flight back to Houston, and when I leveled off, I had my normal cruise TAS of 172 knots ? and a ground speed of 210! (This was with WOT, 2350 RPM, 8.2 gph, showing 68% power). The time to destination was about 30 minutes ? sweet!

As nice as the cruise was (smooth, cool, clear, with downtown Houston visible from 90 miles away?), the descent was magic. When the ?time to go? predictor on my 396 showed me with 8 minutes to the Class B, with 6,000? to lose, I popped off the Altrak and trimmed nose down for 1,000fpm. As the plane accelerates, the descent slows, so a little more nose down goes in as I look for the 200 KTAS redline I have tested for flutter a little above that, and have decided to salute the designer?s intentions!). As the descent rate and speed pick up, I was getting 230 knots over the ground ? hey, it?s kind of cool to think that you might have to worry about the speed limit below 10K?! With the descent comes thicker air, so the % power climbs on the EFIS, and when it hits 75%, I begin to throttle back, leaving the RPM?s where they are. The descent continues with minor adjustments to pitch to keep the speed in limits while slowly bringing the throttle back to stay at 75%. Every few thousand feet, the engine picks up just little roughness, so I nudge the mixture just a little richer to smooth things out. Reaching the Class B, I am nicely below the first floor, and on target to be beneath the 2,000? portion where the destination resides.

As I get to 2,000?, I put in a little nose up trim, leveling off at 1,800? with the power at a perfect 75%, the mixture as lean as I get can get it, and the trim set, so punch the Altrak again to make sure I stay below the Class B, and with five minutes to go, it?s time to monitor the local traffic and get ready to slow down. The air was smooth the whole way down, and once again, I am amazed at the speed and handling of the RV-8. As I approached the field, I recognized John, another new RV-8 owner, on the CTAF. He followed me in for a little ramp flying ? someone watching us would think we?d just flown for the first time ? with ear to ear grins and the enthusiasm of school boys.

Keep pounding those rivets guys!

Paul
 
Last edited:
Groundspeed

I once was working on cutting off two feet of concrete from the floor of my mate's hangar, under the door, so I could insert a box gutter drain and repour the concrete. It was a dreadful day with gales and passing showers.
When I finished I felt I deserved a fly and the wind was down the strip, so off I went in Gerry's -8 VH-SOA.
Airborne heading SW I found the ground speed around 130KT so I turned until the GPS showed me into wind and climbed to 10,000'- (the no-oxygen limit in Aus. It doesn't need to be higher as the highest dirt is 7,200'.)

Once I was well down wind, I turned onto the reciprocal heading and headed home, descending on the VNE.

The best groundspeed I saw was 264KT and I was all buzzing, however, the return was so fast that I arrived over Gerry's strip at 6,000'. But I did see a personal best in Gerry's -8 that I have yet to beat in my -7.

Pete.
 
Ironflight said:
Weathermeister advised going out low and coming back high (normal for the winter), and boy, was it right on. The headwind at 4500? on the way out was actually much lower than I expected, so I continued the climb, only to see the headwind component go through the roof when I got above 5,000 ? so I headed back down and was satisfied to call it even. I like to get higher to save on fuel for the same TAS, but there?s no point in doing that if you?re going to lose it on time?
Click to expand...
Weathermeister doesn't lie! The "Flight Optimizer" really kicks butt for this type of thing. Every once in a while I cave and find myself doubting it, only to find it was right all along. It's the reason I built it -- to take the guesswork out of the equation! :D

Great stuff. When you're pushing 30 mpg it really is sweet!
 
Paul
If you ever fly into the Bay Area give us other guys a break and slow down.
Sure you're legal and its a lot of fun to fly around with your hair on fire but remember your RV8 is a little target and not everyone is on Bay Approach with traffic advisories. :(
Tom
RV3
Bay Area
 
tin man said:
Paul
If you ever fly into the Bay Area give us other guys a break and slow down.
Tom
Click to expand...

Of course Tom, by the time I'm down to 2,000', and below the Class B, with 75% power, the IAS is down to about 150-155 Kts.

Paul
 
As the descent rate and speed pick up, I was getting 230 knots over the ground ? hey, it?s kind of cool to think that you might have to worry about the speed limit below 10K?

All speed limits are based on indicated airspeed, not groundspeed. However, 230 knots across the ground is still pretty impressive!
 
Paul,

Pls keep the commentary coming. I for one enjoy reading threads of this nature as I?m maybe just a handful of months away from 1st flight. I pretty much have the same setup as you so the settings, performance numbers and their application to real trips is motivational.

Best
 
You must log in or register to reply here.