H9's Sundowner

[Jkoch713]

sparky,
could you provide the link to the video?

Justin

[Sparky69]

Justin,
Not computer smart enough to do that. I just posted on the thread so it should be back at the top of the stack.
Sparky

[Captinjohn]

	Quote: Originally Posted by rcign
	Almost all the F1GT planes fly like big sport planes, no bad habits...We took our Kelly F1GT to a sport field in Chino Valley and flew it in wind that had the other sport flyers sitting and watching...Loops, rolls, knife edge, hammerheads, etc...It was a big hit with the locals....It took 3rd in Silver in it's first race in about 15 years. (It's the second Kelly ever built, still going strong) ..It would have been first but for a start cut...It was the pilot's first organized pylon race with a new caller.... You just need to watch the landing speed, they glide and glide and glide.......

RCIGN: You got somegood looking airplanes..ect in this forum! Capt,n

[videocruzer]

i have a siato 220 in mine
the 18x10 was 7500 and was 124mph on the gps.
i used a 16x16apc tonight the static was very close to 7500 on the ground but man is it ever faster in the air.
it really unloads and sounds awesome. I never got a chance to mount the gps tonight mainly cause i left it at home .

[statbeast]

I would love to see this plane fly on a Saito 220. That sounds like a great combo.

[mfuess]

	Quote: Originally Posted by videocruzer
	i have a siato 220 in mine the 18x10 was 7500 and was 124mph on the gps. i used a 16x16apc tonight the static was very close to 7500 on the ground but man is it ever faster in the air. it really unloads and sounds awesome. I never got a chance to mount the gps tonight mainly cause i left it at home .

I can't get the math to come out right according to your info. A 10 pitch prop has to spin up to 13,100 RPM in order to achieve 124 MPH. I don't think a Saito 220 can turn up that fast, and last very long. But maybe it CAN?

18x10x7500RPM=71.03 MPH,
plus add 10% for airborn unloading factor@8250RPM, that equals 78.13 MPH

even at 30% unload (full throttle dive) is 9750RPMx18x10prop=92.33 MPH

Help me out here...

[Sparky69]

Is that some sort of max speed in a dive or level flight?
According to USRA rules the engine is too big (this is the USRA racing forum) . A Moki 2.1 is allowed which I have extensive flight testing on using the Eagle tree system. Do you have inflight RPM and Indicated airspeed (IAS)? I did not use a GPS in mine. It does sound a wee bit fast for that prop without some wind assistance. What brand of prop?
I was seeing a little over 9300 RPM in level flight on course with a APC 17x12. What does the math say I should be doing? I haven't been able to find any math model set up for inflight RPM computations.
The more I have flown the Sundowner the more I have liked it. I tought it would not handle the in flight loads from this big engine but so far it has withstood all the inflight stresses with no indications of problems.
Sparky

[videocruzer]

mfuess i dont know what to tell you
the gps i used is a Garmin 60CSx. Pretty much top of the line as hand helds go.
the gps also recorded about 8 miles... the flight was short maybe 5 or 6 minites
the winds that day were maybe 5 to 10mph.
also the flight path, about 5 to 10degree dives at the centre line of our field.
i have no intensions of raceing the plane... I bought the engine for the sound and the plane for the looks.
statbeast
the 18x10 zoar pulls like a truck in the verticle and the 16x16apc looses steam at about the 800 in the verticle
with the 18x10 it sounded great but man with the 16x16 the way and sound it makes when it unloads just brings a smile to my face .
I have an onboard live video feed and i am waiting on my dragon OSD to come,
sparky i dont have to post here if it offends you. I am working on a new camera mount system that I hope will get the vibration out of the picture.

[Sparky69]

Video,
No man I am not offended in the least by your post. I know that there are lurkers who don't read the whole thread and might think this engine and prop combo might be allowed in the USRA class of racing. I know what you mean though about a pretty good ARF to go fast with. If you want to take it to another level why don't you come race with us?
If you get a chance see what an APC 17x10 will do. I would love to see the numbers.
Sparky

[videocruzer]

tonight i put the gps in the sundowner with the saito 220. just over 8000 static with a 16x14 apc on 30% heli. winds were barely moving the flag i would say 1 to 2 mph.
i also made sure not to dive at all on the gps flight. the full throttle dive to the centre line of the run way was no more then about 10 degrees.
I had to look twice at the gps... the max recorded speed was 246kph or 146mph.
max fpm was 2174fpm but it starts to run out of steam around 800'.
needles to say i am pretty happy about the speed and the sound is awesome.
one other note the 220 i have has the stock carb, and its the 180 carb.
also at 50% throttle it works out to 1 oz a minite. the plane is a blast to fly but it will snap hard when flying under half throttle with full rates on if you get to heavy on the elevator.

I found a site that you can put the pitch and rpm and it gives you the speed, but the numbers are wacked and the gps does not lie.

[rcign]

Don't know about GPS numbers, but 14 pitch at 8000 rpm can't be that fast unless you can rewrite the laws of physics.....Pitch x rpm x .00095 minus a few percent for drag will give you a good approximation....Look elsewhere in the thread, a Sundowner with a 2.4 and tuned pipe was not even close to that....Too bad they won't go that fast
Nobody testing with radar has come even close....Our T6s turn 92 to 9600 in the air...Props are 14 pitch...Speed is WAY slower than that..On radar...At the end of the straightaway...

[mfuess]

14 pitch at 8000 RPM=106.06 MPH, not even factoring in drag. Even if you add 10% for unloading that's still only 116.67 MPH.