X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=dLzYZ9Rb c=1 sm=1 tr=0 a=aTSfdvWe1zVojN8rqXXKsg==:117 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=x7bEGLp0ZPQA:10 a=kj1derGAFDYA:10 a=oexKYjalfGEA:10 a=pGLkceISAAAA:8 a=Ia-xEzejAAAA:8 a=HZJGGiqLAAAA:8 a=UKPAHat8AAAA:8 a=pdU0Jt0zFC8eBUU-UQIA:9 a=sZEIDZYBNsXhkywm:21 a=NjOFUduYzB1W1No9:21 a=QEXdDO2ut3YA:10 a=DpM6R7hEn-wlWRZbTWYA:9 a=OOtJopYr5Vz6HWCe:21 a=SSCD-P6lgKknnqnJ:21 a=Twd7Hu_GYB4KHzaY:21 a=Urk15JJjZg1Xo0ryW_k8:22 a=Fc6xXSS-RxGHxrvp76Qp:22 From: "alex alex.molteno@gmail.com" Received: from mail-wr1-f46.google.com ([209.85.221.46] verified) by logan.com (CommuniGate Pro SMTP 6.2.12) with ESMTPS id 12432209 for flyrotary@lancaironline.net; Mon, 08 Apr 2019 20:56:14 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.221.46; envelope-from=alex.molteno@gmail.com Received: by mail-wr1-f46.google.com with SMTP id w10so18549729wrm.4 for ; Mon, 08 Apr 2019 17:56:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=VMgZtj1iFCoNqJXiHBMIa2ryQoS3DukIpoAeBH6Nn98=; b=R443eZC/VdZKQJk6+YZkG1zFmFF7KYytUAQC9sI8aFrFitOGD0yCrkk9iQmq9o1QeO x3bUoMy9x7jIP3oLvChjfODklVTmDuUSS+Doq5jNi3wjOYw5kvdAWA9t/USIZYojiD0H 50mnTFbNsU2lTts+J34ypiypC4oG4a8ATOFQ5u86MPA1bGvpmMB8CB7KDzIEC2lW9GCh I0bIP1y1Vx8n/rt47ajA0qzF2p6FwyKkbUVNY0i62Q1025CLy9ue12JlGzZO5Mb8UzJu dLQgt4NIOZkjdcW0RaASrwifv93wqosNOpfq4RDPrpml7vXNAb0uOneYshqnsQ0FtMdE /KqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to; bh=VMgZtj1iFCoNqJXiHBMIa2ryQoS3DukIpoAeBH6Nn98=; b=X6kJz4oRbXfuS4FUfNre3nAFyNOfIckMxgNmMv6xzLvNRMgIGIIZtybd2aMJQ9CvD/ FqVXxutSpAPG1jIvUnZhRulSTS90XMYxiw2xs6WivZquTOxmjwqboC/pZHlbh1WDaBfu ueaM9yZ4aTA+ttU5bhpDB+vxqSecj2U3mQ7wa96sO0YBgw3azQoZEZ4WHkmXd3wI2X0t slVdLjMOPtXAmO5h0m3OMsZ0UEqCx+I4vlUrg/OoITNwF0eMJ0YXOsULVjCmNJyzchy1 JXsf4kW9rEL8i1KFadgdfP5P/A4rvUaJB+kObGbNNam4Ri8ZMgeGeZQe944I4TQ2hutH 31mg== X-Gm-Message-State: APjAAAWs3hJrB6gKxy3DgMD7gRYAiQmBCkav7avDSt7pOU2G61IdSFEf 1SuLRc80mCe4jXwEIx+tzlw6aN4HXQXo5PH8olOrDRWm X-Google-Smtp-Source: APXvYqx+TiirrrZdIw7rFv/3MuVbJhcBEhLCJbEVjDyVxFCCNRGfVU1n7T3XGY3uBXaSQXOLjFdVb8sV88+d2CjtDAE= X-Received: by 2002:a5d:6a89:: with SMTP id s9mr4980437wru.58.1554771357892; Mon, 08 Apr 2019 17:55:57 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: Date: Mon, 8 Apr 2019 19:55:45 -0500 Message-ID: Subject: Re: [FlyRotary] Re: Electric constant speed props To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary="0000000000007e85f105860e6a53" --0000000000007e85f105860e6a53 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable I'd spoken to Martin at sun n fun last year about an airmaster prop and he recommended his electric hub with whirlwind blades, AP533 blades i think it was. You can choose any blades you like on his hub. If going over 220hp with a p-port he recommended going with 3 blades to soak up the additional hp FWIW. It all sounded good until the price, about $14k with shipping was too big a chunk for me to consider, nice looking equipment though, expecially the electric governor Alex Molteno On Mon, Apr 8, 2019, 09:28 James Whitehurst flyboyusvi@gmail.com < flyrotary@lancaironline.net> wrote: > Hi guys, I just spoke with Martin of Airmaster at Sun n Fun. He seems to > be one of the main engineers(very knowledgable). I asked him if he could > make me 2, C/S, electric, reversible, feathering props for my twin 350 hp > rotary amphibian. The bottom line is yes, 5 blade to absorb the hp, > about45#, around the same price as my MT quote but they will have to wor= k > out the details of my operational control requirements over the next few > months.( I am at least 2 years from needing the props.) Electric seems to > be where I am headed unless someone out there knows where I can get 2 > Mistral PSRU's. James whitehurst > > On Fri, Apr 5, 2019, 21:14 Charlie England ceengland7@gmail.com < > flyrotary@lancaironline.net> wrote: > >> Well, now I know that I should proof read before hitting send.... >> >> On 4/5/2019 3:46 PM, Charlie England ceengland7@gmail.com wrote: >> >> I had a similar experience with one of the guys with AutoPSRUs in the al= t >> engine tent a couple of years ago. Tried to sell me a reduction for a >> rotary, and it was blatantly obvious that he was clueless. But their who= le >> concept has major flaws, so I shouldn't have been surprised. >> >> As a FWIW, if you're serious about a controllable prop it might be worth >> finding someone else in the company to question. My experience at airsho= ws >> in general is that you might get the CEO, or you might get a guy that's >> filling in for his friend who went to take a leak. :-) I know, because >> about 25 years ago, I was occasionally that guy on occasion. :-) >> >> Charlie >> >> On 4/5/2019 8:47 AM, Samuel Hodges samueln462wp@att.net wrote: >> >> Went to Sun n Fun and talked to a Aeromaster representative to collect >> information and data on their Electric constant speed prop combinations. >> After waiting a little while a representative of the company approached = as >> asked what he can do for me. I replied that I am extremely interested in >> their design and would like further information. I was asked about my >> aircraft engine installation, I explained to him about the Rotary and wh= at >> my RPM requirements would be. His response went something like this " Do >> you know how much this cost? it will probably double the cost of your >> installation/plane" I immediately took this as an insult and replied " y= ou >> know nothing of me, my finances, nor my plane" as I walked past him I >> padded him on the arm and said " keep your freakin prop, you just saved = me >> a lot of money" but I didn't say freakin. One thing I did find out is th= at >> it would be around 26lbs, well worth the trip, wouldn't you agree? >> >> Sam >> >> On Tuesday, April 2, 2019, 07:27:12 PM EDT, Bobby J. Hughes >> bhughes@qnsi.net >> wrote: >> >> >> >> Climb at 6800/ 2100 rpm >> >> Correction 6000/ 2100 rpm. >> >> Bobby >> >> Sent from my iPhone >> >> On Apr 2, 2019, at 5:46 PM, Bobby J. Hughes bhughes@qnsi.net < >> flyrotary@lancaironline.net> wrote: >> >> Bill, >> >> Most takeoffs have been at 7000/2400 rpm with MP between 34-38=E2=80=9D = to >> pattern. >> Climb at 6800/ 2100 rpm >> >> Cruise at 5200/ 1824 or 4800/ 1624 rpm depending on my desired fuel burn >> and airspeed. Most cross country flight are at 28-30=E2=80=9D MP and wi= th F/A >> 15.8. Or 13.5 for higher MP. >> >> Bobby >> >> Sent from my iPhone >> >> On Apr 2, 2019, at 5:13 PM, William Jepson wrjjrs@gmail.com < >> flyrotary@lancaironline.net> wrote: >> >> Bobby, You push it fairly hard with your supercharged engine too. What >> cruise RPM are you running? P.Sport always tried to tune for lower RPMS = and >> higher power to avoid the torsional vibration problems. With boost you c= an >> make more power at lower RPMs which is a plus in this case. The rotary = is >> tough, the engine will tolerate a lot, but the high revs for long period= s >> is what causes the need for attention to torsionals. BTW I moved and had= to >> take a break from my redrive efforts, but am getting back to it. Got som= e >> good ideas today from Mark Hatch, Everett's son. >> Bill >> >> On Tue, Apr 2, 2019 at 2:02 PM Bobby J. Hughes bhughes@qnsi.net < >> flyrotary@lancaironline.net> wrote: >> >> >> My MT weighs 42#=E2=80=99s. The hub is heavy, blades are light weigh. Ge= ar >> lashing appears to have increased a little over the first 500 hours. End >> play is about 5 thousandths with original snubber. >> >> Bobby >> >> Sent from my iPad >> >> On Apr 2, 2019, at 3:48 PM, William Jepson wrjjrs@gmail.com < >> flyrotary@lancaironline.net> wrote: >> >> Sam, >> I am working with some originators of Powersport. The weight of your >> build makes a big difference on the use of a constant speed. Also in the >> case of the rotary the quality of your muffler! Sound levels really effe= ct >> your comfort on longer flights. Mufflers for rotaries are tough, I alrea= dy >> have 1 failed design to my (bad) credit. The original Powersport designs >> used the light weight and flexibility of a wood prop to their advantage. >> Those engines were tuned for max power at 6500 RPM. The reductions were >> about 1.85 to 2.2:1. suitable for the lower power peak. Torsional vibrat= ion >> issues also favored a wood prop. How heavy is the electric Airmaster? >> MOST engines including the rotary are helped by a variable pitch prop. >> Whether the combination is safe depends on the reduction drive, ratio, a= nd >> weight of the prop on the output shaft. Powersport's owners noted >> significant torsional vibration problems with every planetary gear set, >> (even their own custom made straight cut planetary). Their later stiff >> model internal ring gear reduction gearbox put the resonances out of the >> normal range for the rotary. Prior to that the only problem free build w= ith >> a planetary was when they built a pendulous damper system (like a big >> radial engine uses) which worked great but was so expensive they figured >> they would never sell an engine. So if you are running a planetary >> reduction you need to keep the weight down as much as you can. Find out >> what the Airmaster weighs. The amount that it exceeds your wood or >> carbon fixed blade prop is your risk factor. The advantage is to use a l= ow >> cruise rpm that takes advantage of the props flexibility. As a thrust >> producing device it is better, there is no doubt. If it is very heavy >> though it may cause problems that aren't obvious as to origin. Torsional >> problems may take hundreds of hours to develop, or something may break t= he >> first week. Just be wary. Always keep track of things like changes in >> output shaft end play and backlash. You can make the change, and see >> excellent results but go in with your eyes open. Lots of people will tel= l >> you this is nervous nelly stuff, but the guys at P.S. probably had more >> hours running and testing rotaries AT HIGH OUTPUT levels than anyone oth= er >> than Mazda. >> Bill Jepson >> >> On Tue, Apr 2, 2019 at 6:34 AM Samuel Hodges samueln462wp@att.net < >> flyrotary@lancaironline.net> wrote: >> >> Lately I have been considering an Airmaster electric constant speed pro= p >> to help achieve the rotaries true potential. I am asking for insight to >> help me make this decision. I'm not sure if the benefits of a constant >> speed out weight the cost, please help. >> >> Sam >> RV-7A >> Renesis >> >> >> >> --0000000000007e85f105860e6a53 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
I'd spoken to Martin at sun n fun last year abou= t an airmaster prop and he recommended his electric hub with whirlwind blad= es, AP533 blades i think it was. You can choose any blades you like on his = hub. If going over 220hp with a p-port he recommended going with 3 blades t= o soak up the additional hp FWIW. It all sounded good until the price, abou= t $14k with shipping was too big a chunk for me to consider, nice looking e= quipment though, expecially the electric governor
Alex Molteno

On Mon, Apr 8, 2019, 09:28 James Whitehurst flyboyusvi@gmail.com <flyrotary@lanc= aironline.net> wrote:
Hi guys, I just spoke with Martin of Airmaster at Sun n Fun. He= seems to be one of the main engineers(very knowledgable). I asked him if h= e could make me 2, C/S, electric, reversible, feathering props for my twin = 350 hp rotary amphibian. The bottom line is yes, 5 blade to absorb the hp, = about45#, around the same price as my MT quote=C2=A0 but they will have to = work out the details of my operational control requirements over the next f= ew months.( I am at least 2 years from needing the props.) Electric seems t= o be where I am headed unless someone out there knows where I=C2=A0 can get= 2 Mistral PSRU's. James whitehurst

On Fri, Apr 5, 2019, 21:14 Charlie E= ngland ceengland7@gmail.com <flyrotary@lancaironline.net> w= rote:
=20 =20 =20
Well, n= ow I know that I should proof read before hitting send....

On 4/5/2019 3:46 PM, Charlie England ceengland7@gmail.com wrote:
=20
I had= a similar experience with one of the guys with AutoPSRUs in the alt engine tent a couple of years ago. Tried to sell me a reduction for a rotary, and it was blatantly obvious that he was clueless. But their whole concept has major flaws, so I shouldn't have been surprised.

As a FWIW, if you're serious about a controllable prop it might be worth finding someone else in the company to question. My experience at airshows in general is that you might get the CEO, or you might get a guy that's filling in for his friend who wen= t to take a leak. :-) I know, because about 25 years ago, I was occasionally that guy on occasion. :-)

Charlie

On 4/5/2019 8:47 AM, Samuel Hodges samueln462wp@att.net wrote:
=C2=A0Went to Sun n Fun and talked to a Aeromaster representative to collect information and data on their Electric constant speed prop combinations. After waiting a little while a representative of the company approached as asked what he can do for me. I replied that I am extremely interested in their design and would like further information. I was asked about my aircraft engine installation, I explained to him about the Rotary and what my RPM requirements would be. His response went something like this " Do you know how much this cost? it will probably double the cost of your installation/plane" I immediately took this as an insult and replied " you know nothing of me, my finances, nor my plane&= quot; as I walked past him I padded him on the arm and said " keep your freakin prop, you just saved me a lot of money" but I didn't say freakin. One thing I did find out is that it would be around 26lbs, well worth the trip, wouldn't you agree?

Sam =C2=A0 =C2=A0=C2=A0

On Tuesday, April 2, 2019, 07:27:12 PM EDT, Bobby J. Hughes bhughes@qnsi.net <flyrotary@lancaironline.n= et> wrote:



Climb at 6800/ 2100 rpm=C2=A0

Correction 6000/ 2100 rpm.=C2=A0

Bobby=C2=A0

Sent from my iPhone

On Apr 2, 2019, at 5:46 PM, Bobby J. Hughes bhughes@qnsi.net <flyrotary@lancaironline.net> wrote:

Bill,

Most takeoffs have been at 7000/2400 rpm with MP between 34-38=E2=80=9D to pattern.
Climb at 6800/ 2100 rpm=C2=A0

Cruise at 5200/ 1824 or 4800/ 1624 rpm depending on my desired fuel burn and airspeed. =C2=A0Most cross country flight are at 28-30=E2=80= =9D MP and with F/A 15.8. Or 13.5 for higher MP.=C2=A0

Bobby

Sent from my iPhone

On Apr 2, 2019, at 5:13 PM, William Jepson wrjjrs@gmail.com <flyrotary@lancaironline.net> wrote:

Bobby, You push it fairly hard with your supercharged engine too. What cruise RPM are you running? P.Sport always tried to tune for lower RPMS and higher power to avoid the torsional vibration problems. With boost you can make more power at lower RPMs which is a plus in this case.=C2=A0 The rotary is toug= h, the engine will tolerate a lot, but the high revs for long periods is what causes the need for attention to torsionals. BTW I moved and had to take a break from my redrive efforts, but am getting back to it. Got some good ideas today from Mark Hatch, Everett's son.= =C2=A0
Bill

On Tue, Apr 2, 2019 at 2:02 PM Bobby J. Hughes bhughes@qnsi.net <flyrotary@lancaironline.net> wrote:

My MT weighs 42#=E2=80=99s. The hu= b is heavy, blades are light weigh. Gear lashing appears to have increased a little over the first 500 hours. End play is about 5 thousandths with original snubber.=C2=A0

Bobby

Sent from my iPad

On Apr 2, 2019, at 3:48 PM, William Jepson wrjjrs@gmail.com <flyrotary@lancaironline.net&= gt; wrote:

Sam,
I am working with some originators of Powersport. The weight of your build makes a big difference on the use of a constant speed. Also in the case of the rotary the quality of your muffler! Sound levels really effect your comfort on longer flights. Mufflers for rotaries are tough, I already have 1 failed design to my (bad) credit. The original Powersport designs used the light weight and flexibility of a wood prop to their advantage. Those engines were tuned for max power at 6500 RPM. The reductions were about 1.85 to 2.2:1. suitable for the lower power peak. Torsional vibration issues also favored a wood prop. How heavy is the electric Airmaster<= /span>? MOST engines including the rotary are helped by a variable pitch prop. Whether the combination is safe depends on the reduction drive, ratio, and weight of the prop on the output shaft. Powersport's owners noted significant torsional vibration problems with every planetary gear set, (even their own custom made straight cut planetary). Their later stiff model internal ring gear reduction gearbox put the resonances out of the normal range for the rotary. Prior to that the only problem free build with a planetary was when they built a pendulous damper system (like a big radial engine uses) which worked great but was so expensive they figured they would never sell an engine. So if you are running a planetary reduction you need to keep the weight down as much as you can. Find out what the Airmaster<= /span> weighs. The amount that it exceeds your wood or carbon fixed blade prop is your risk factor. The advantage is to use a low cruise rpm that takes advantage of the props flexibility. As a thrust producing device it is better, there is no doubt. If it is very heavy though it may cause problems that aren't obvious as to origin. Torsional problems may take hundreds of hours to develop, or something may break the first week. Just be wary. Always keep track of things like changes in output shaft end play and backlash. You can make the change, and see excellent results but go in with your eyes open. Lots of people will tell you this is nervous nelly stuff, but the guys at P.S. probably had more hours running and testing rotaries AT HIGH OUTPUT levels than anyone other than Mazda.
Bill J= epson

On Tue, Apr 2, 2019 at 6:34 AM Samuel Hodges samueln462wp@att.net <flyrotary@lancaironline.net> wrote:
=C2=A0Lately I have been considering an Airmaster electric constant speed prop to help achieve the rotaries true potential. I am asking for insight to help me make this decision. I'm not sure if the benefits of a constant speed out weight the cost, please help.

Sam
RV-7A
Renesis=C2=A0


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