Bayou Bert

Bayou Bert

Well Known Member
Getting ready to start on RV9A. Being a low time C150/152 pilot I figured
the 9A would fit the bill. Mission is a touring airplane for seeing the US.
So, with an IO320..FP..slightly below gross at 8 to 10K what is a good
average cruise at 75%? I know what the specs show just would like to
know how close to real world numbers.
I live near Baton Rouge, so to throw out a trip, say to Denver...1300 miles,
should I be able to beat the airlines, avg 10 hrs one way with TSA and 1200.00 for 2 people RT.
 
Bayou Bert said:
Getting ready to start on RV9A. Being a low time C150/152 pilot I figured
the 9A would fit the bill. Mission is a touring airplane for seeing the US.
So, with an IO320..FP..slightly below gross at 8 to 10K what is a good
average cruise at 75%? I know what the specs show just would like to
know how close to real world numbers.
I live near Baton Rouge, so to throw out a trip, say to Denver...1300 miles,
should I be able to beat the airlines, avg 10 hrs one way with TSA and 1200.00 for 2 people RT.
Click to expand...

I usually fly below 65% power in cruise. I file at 140 kts. I made a time/range chart as a motivator for myself. I just shifted the center to Baton Rouge. Below is the chart for you. Each ring is one hour of flight. My rule of thumb to compare driving/RV/airline travel time is to use the ratio: 9/3/1. Flying RV you need to add travel to the airport, preflight and rest/fuel stop. Flying commercial needs to add trip to the airport, security check, and boarding time.


RV9A%2520range%2520map%2520-%2520Microsoft%2520Streets%2520%2526%2520Trips%25201112013%252073143%2520AM.bmp.jpg
Microsoft Streets and Trips
 
Last edited:
Take a Look at Your Engine Manual

Bert:
I have an O320 in my 9A, so I can't speak specifically about the performance of the injected version. On mine, the manual says full throttle at 9,000 and 10,000 will yield 73.5 and 70.8 per cent respectively. That said, I normally cruise in the 8,000-10,000 range at 2450 RPM (just short of WOT). My TAS at that setting is in the range of 151-154 knots at gross. It's a great traveling machine(and a fine instrument platform - if you plan to continue to expand your horizons).
Terry, CFI
RV9A N323TP
 
How much fuel do you want to burn?

The answer has several variables. One constant speed prop or fixed pitch, another is the position of the mixture or how much fuel you want to burn.

I have over 2,600 hours over the past 15-years on my 320 powered constant speed prop RV-6. Do not let anyone tell you that the top or cruise speed on the -9(A) is less than the -6(A) at the same power. Yes the slow speed of the -9(A) is lower.

Turning 2,300 RPM at WOT will yield 150 KTAS at a lean mixture and fuel burn of 7 GPH. Turning the mixture in to a rich mixture will give you 160 KTAS at 8.5 GPH. Only change is the mixture setting and that changes the fuel burn.

For me, 1.5 GPH is not worth the extra speed on a normal Cross-Country flight. Now when I am I am in a hurry (that is almost never) burn the extra fuel and get to where you are going a few minutes (yes just a few minutes) faster.
 
My numbers are about the same as the rest, O320 160hp wood prop, I plan my trips for 140kts at around 65% power. We now have 720hrs and six years together and I am still in awe of the machine. :)
 
pretty much identical speed.....

terrykohler said:
Bert:
I have an O320 in my 9A, so I can't speak specifically about the performance of the injected version. On mine, the manual says full throttle at 9,000 and 10,000 will yield 73.5 and 70.8 per cent respectively. That said, I normally cruise in the 8,000-10,000 range at 2450 RPM (just short of WOT). My TAS at that setting is in the range of 151-154 knots at gross. It's a great traveling machine(and a fine instrument platform - if you plan to continue to expand your horizons).
Terry, CFI
RV9A N323TP
Click to expand...

0-320 A ( 7.5:1) with FP sensenich 79 pitch. can't seem to get 2450, more like 2350, but yields 152 kts on the GPS @ WOT at 6,000 and over.
 
Cruise Airspeeds

I normally fly at 150 KIAS true. Keep in mind that at econ fuel flows, for max range distances the most important tool in the airplane for us old guys is the Gatorade P bottle!:)
 
Ted, nice chart. That is a great way of showing guys like me that are not finished building where we can go! I will make my own in photoshop and put the rings on a second layer so I can move it around. Thanks for the idea.
 
Excellent chart Ted. Another addition to my bookmarks. Now if I could only get Google Maps to overlay circles like those.
 
Online range ring generator

And a few minutes after I post my reply, I find a reasonably equivalent range ring map generator:

http://www.gpsvisualizer.com/calculators

Near the bottom, it has an option for drawing range rings. Feed it your airport code and a comma-separated list of ranges. It has no problem with the "nm" suffix for nautical miles, so I just feed in a list of multiples of 140nm for 140 kts. Out it spits overlays on top of Google Maps.
 
Great Link

I like this link. Draws a nice editable, scrollable and zooming map in seconds. Here is the one I just did for my local airport (CCB was not available so I used KONT). Way Cool!

And a few minutes after I post my reply, I find a reasonably equivalent range ring map generator:

http://www.gpsvisualizer.com/calculators

Near the bottom, it has an option for drawing range rings. Feed it your airport code and a comma-separated list of ranges. It has no problem with the "nm" suffix for nautical miles, so I just feed in a list of multiples of 140nm for 140 kts. Out it spits overlays on top of Google Maps.
Click to expand...

RV9A 140nm Range Chart 2.jpg
 
My numbers are about the same as others. I flew my friends 150 the other day and I didn't think it would ever get off the ground and seem to just drag through the air. When I was taking flying lessons in a 150 it didn't seem so bad but after flying an RV9A you will think you are in a jet! :)
 
I have an O-360 and CS prop and my numbers are pretty much the same as the O-320s are getting.

Our numbers become more impressive (at least to me) when flying with a friend in his Archer III. I look at his fuel flow and his TAS and have to force myself not to say anything. Plus it just is not as much fun and that is the key to me.
 
With my Catto 3-blade, I'm seeing 147 to 150kts at 2500 RPM and 4000MSL. That's around 75% power. I agree with the others on 140kts TAS being a good number to use. That let's you throttle back a bit for both better economy and less noise.
 
That is probably closer to 80% power, and a bit slower than I have seen with known calibrated ASI/TAS but that might be a function of the three blade Catto prop. They look sexy as, but are slower, same story with a -7 here.

They do well up a bit higher I have found. Good bang for buck machines!
 
The -9(A) is a great plane.

Here is a trip write-up I did back in November that will give you an idea of what to expect. Never mind I have an O-360 in the plane as it started life with a 135 HP O-290-D2 that I would cruise all over the place at 140 knots.
 
You must log in or register to reply here.