Today's Message Index:
----------------------
1. 06:03 AM - Re: Best Prop for HR 2 (n395v)
2. 06:27 AM - Re: Re: Best Prop for HR 2 (Stuart Hutchison)
3. 07:45 AM - Re: Re: Best Prop for HR 2 (Rob Ray)
4. 02:43 PM - Re: Re: Best Prop for HR 2 (Tom Gummo)
Message 1
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| Subject: | Re: Best Prop for HR 2 |
I can't speak for a Harmon Rocket but a lot of F1s had a terrible vibration (prop-beat
or whatever) that was intolerable with a 2 blade hartzell. Mine was one
of them. Changed to a 3 blade MT (one of Jim's)
Problem was gone and plane was much quieter. It did however have measurable loss
of performance in climb and cruise as well as top speed.
I think Tom Gummo has a 4 blade MT on his Harmon and I recall somewhere he called
it the slowest Rocket in the West.
In my opinion the less blades the better for performance and cost. As to the manufacturer
I have heard few complaints about Hartzell or MT. Never heard of the
brand you are considering.
--------
Milt
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=339741#339741
Message 2
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| Subject: | Re: Best Prop for HR 2 |
Should have better climb on 3 blades, but lower top speed (extra blade = more drag).
2 for go, 3 for show!
Kind regards, Stu
www.mykitlog.com/rockfly
Sent from my iPhone
On 13/05/2011, at 11:01 PM, "n395v" <Bearcat@bearcataviation.com> wrote:
>
> I can't speak for a Harmon Rocket but a lot of F1s had a terrible vibration (prop-beat
or whatever) that was intolerable with a 2 blade hartzell. Mine was
one of them. Changed to a 3 blade MT (one of Jim's)
>
> Problem was gone and plane was much quieter. It did however have measurable loss
of performance in climb and cruise as well as top speed.
>
> I think Tom Gummo has a 4 blade MT on his Harmon and I recall somewhere he called
it the slowest Rocket in the West.
>
> In my opinion the less blades the better for performance and cost. As to the
manufacturer I have heard few complaints about Hartzell or MT. Never heard of
the brand you are considering.
>
> --------
> Milt
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=339741#339741
>
>
>
>
>
>
>
>
>
>
>
Message 3
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| Subject: | Re: Best Prop for HR 2 |
Best HR2 prop? The one that works:) seriously, the prototype HR2 has a Hartzell
2 blade sold by John. After testing 2 props on mine and chatting with other folks,
here is my 2cents.
I had a "D" twist Hartzell 2 blade on mine optimized for 2500 RPM. Their is also
a "J" twist optimized for 2350 RPM. Hartzell also makes a 2blade Blended airfoil
prop for the Rocket currently flown by Tom Martin. The MT would be smoother
but a bit slower at top end, the 3blade Hartzell is too heavy.
I would either go with the J twist or BA 2 blade from Hartzell purchased through
Harmon (J) or Team Rocket (BA)
Smokey
Sent from my iPhone
On May 13, 2011, at 9:01, "n395v" <Bearcat@bearcataviation.com> wrote:
>
> I can't speak for a Harmon Rocket but a lot of F1s had a terrible vibration (prop-beat
or whatever) that was intolerable with a 2 blade hartzell. Mine was
one of them. Changed to a 3 blade MT (one of Jim's)
>
> Problem was gone and plane was much quieter. It did however have measurable loss
of performance in climb and cruise as well as top speed.
>
> I think Tom Gummo has a 4 blade MT on his Harmon and I recall somewhere he called
it the slowest Rocket in the West.
>
> In my opinion the less blades the better for performance and cost. As to the
manufacturer I have heard few complaints about Hartzell or MT. Never heard of
the brand you are considering.
>
> --------
> Milt
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=339741#339741
>
>
>
>
>
>
>
>
>
>
Message 4
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| Subject: | Re: Best Prop for HR 2 |
Guys,
I also have a thirty year old engine that I rebuilt. IO-540J4A5 is only 250
HP as well. :-) So who knows what the real HP is? Jim tells me that I
just don't have the HP to use my prop properly.
Part of my slowest is that I built the plane myself and while it turned out
great, I clearly didn't know anything about getting speed out of an
aircraft.
I didn't have an vibration when I had a two blade Hartzell. In my case, the
three blade MT was as fast as the two blade Hartzell.
My four blade MT is slower as I used to cruise:
at 10,500 or 11,500 MSL
Full throttle.
RPM 2100
Leaned to 10.0 to 10.5 GPH
KIAS = 140 True = 180 Knots
with MT prop:
KIAS = 135 True = 170 Knots
For local flying, I really don't see much of a difference.
Numbers are from the top of my head but they are close.
Tom "GummiBear" Gummo
Major USAF Retired, F-4G Wild Weasel Instructor Pilot
Harmon Rocket II, N561FS, 390 hours of the biggest grin
----- Original Message -----
From: "n395v" <Bearcat@bearcataviation.com>
Sent: Friday, May 13, 2011 6:01 AM
Subject: Rocket-List: Re: Best Prop for HR 2
>
> I can't speak for a Harmon Rocket but a lot of F1s had a terrible
> vibration (prop-beat or whatever) that was intolerable with a 2 blade
> hartzell. Mine was one of them. Changed to a 3 blade MT (one of Jim's)
>
> Problem was gone and plane was much quieter. It did however have
> measurable loss of performance in climb and cruise as well as top speed.
>
> I think Tom Gummo has a 4 blade MT on his Harmon and I recall somewhere he
> called it the slowest Rocket in the West.
>
> In my opinion the less blades the better for performance and cost. As to
> the manufacturer I have heard few complaints about Hartzell or MT. Never
> heard of the brand you are considering.
>
> --------
> Milt
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=339741#339741
>
>
> __________ Information from ESET NOD32 Antivirus, version of virus
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> The message was checked by ESET NOD32 Antivirus.
>
>
>
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