X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=E/+zWpVl c=1 sm=1 tr=0 a=VAYHCr8hrj86dj0+EyP22Q==:117 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=x7bEGLp0ZPQA:10 a=Pg7BVu4i2dQA:10 a=xqWC_Br6kY4A:10 a=oexKYjalfGEA:10 a=r77TgQKjGQsHNAKrUKIA:9 a=HZJGGiqLAAAA:8 a=UKPAHat8AAAA:8 a=Ia-xEzejAAAA:8 a=pGLkceISAAAA:8 a=FCQR9JSIp-5XCB4kYNEA:9 a=e_UrZ7f4lcfeMFAs:21 a=FTriabx1hLo5wJ22:21 a=QEXdDO2ut3YA:10 a=QF3R1E_M5XcFmEgEmOwA:9 a=kvHybMcZm25bsJaC:21 a=_W_S_7VecoQA:10 a=Fc6xXSS-RxGHxrvp76Qp:22 a=Urk15JJjZg1Xo0ryW_k8:22 From: "Tracy Hallock thallockster@gmail.com" Received: from mail-oi1-f178.google.com ([209.85.167.178] verified) by logan.com (CommuniGate Pro SMTP 6.2.12) with ESMTPS id 12420066 for flyrotary@lancaironline.net; Fri, 05 Apr 2019 15:21:14 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.167.178; envelope-from=thallockster@gmail.com Received: by mail-oi1-f178.google.com with SMTP id 3so5790471oir.7 for ; Fri, 05 Apr 2019 12:21:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=message-id:from:to:references:in-reply-to:subject:date:mime-version :importance; bh=5KgUg+FeAaJ5qESq+uPaNhGRRJj994SBKtUVZtnaFVI=; b=pQVjtXVmfH9DXw5p6gGiJdLbZYejXpqztVJo2cCgiuTJKik6ZkPdK2VcqpPxN/++WV gpmXWHaJiHwDZvxqR2rTVRMeBHgQrG73Pz+ANX85jaOEsyBP2WnnsjO7LSQnlfbFdGo1 3BkbYLhdXnn6Xt+iO61IlZFfzXlJSng/3An0Wou/CiU8114Tjovko1C0ssPLGvYI7+Z3 HtbL/YWCPfbpWXfgzq67PK8NS0Sknr/Wi1vibPRtO5jT3mRSEhomRvGIKrALc8JKbdZb s/oHZDsTNnK7hZSRPpOKBbRjVku9HXiwvrsLsj8W/vqT7s038/qfdudFGRE5C78Adkbx yXSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:from:to:references:in-reply-to :subject:date:mime-version:importance; bh=5KgUg+FeAaJ5qESq+uPaNhGRRJj994SBKtUVZtnaFVI=; b=syGaMy1BYSuBsUCjw9p9fr/897EqQ0+vijRzQwJg+MQgUwOHPOfCOhZgnfSlKo4EOg wKIUwBoWkOmYVfKKwUTnB95dRs5tr1CYgXZIdgvPlQx6oTj7FvxB3ZDMoEBYqAUs14qg zpHQ3IGmxVcAyQF6JUO6JHz1I8i+iE9zHFKuzBikJpIrUszMW1NJ1+V9nvErJ6VrvtSz JWIOZrSs6F6kLJ/CfZF1BK3FAmNwjPpf3ksm6abFJztJYXBAlp/4d+OqowTRpG3uAodx 2zQR3Zw15qaSyPm3Nfa1sBFx+OFl/3f0Epx04qlPjSMfwPPjf2o3KvSZQ0lCvTEFA2g9 DbHA== X-Gm-Message-State: APjAAAWpSeU5DuX6DMd6zNGiFXO9H/NOuo4LRBWh38BQYiJkvkJ/G+Tn ClQSOG7GuygoV1QkzExdkVeWerwv X-Google-Smtp-Source: APXvYqwVl4VN7mscUY2ijpHiK0t0ZsD9rFH2NPuYkuuVkBy8VyaxCTX7GmCwoM0a8hEnSrATdgbL5A== X-Received: by 2002:aca:e84c:: with SMTP id f73mr8227907oih.163.1554492058031; Fri, 05 Apr 2019 12:20:58 -0700 (PDT) Return-Path: Received: from PCTracyAVR ([2605:6000:f5c1:7800:25ae:a93b:a20b:9ef]) by smtp.gmail.com with ESMTPSA id 131sm8798758oib.51.2019.04.05.12.20.57 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 05 Apr 2019 12:20:57 -0700 (PDT) Message-ID: To: "Rotary motors in aircraft" References: In-Reply-To: Subject: Re: [FlyRotary] Re: Electric constant speed props Date: Fri, 5 Apr 2019 14:20:57 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_022F_01D4EBBA.C961A0D0" X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 16.4.3528.331 X-MimeOLE: Produced By Microsoft MimeOLE V16.4.3528.331 This is a multi-part message in MIME format. ------=_NextPart_000_022F_01D4EBBA.C961A0D0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sam, Well worth the trip. Sometimes it amazes me just how stupid some sales = people can be. You probably dodged a bullet (cost, time to install, = possible problems). Tracy H. From: Samuel Hodges samueln462wp@att.net=20 Sent: Friday, April 5, 2019 8:47 AM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: Electric constant speed props 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 = 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" 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 =20 On Tuesday, April 2, 2019, 07:27:12 PM EDT, Bobby J. Hughes = bhughes@qnsi.net wrote:=20 Climb at 6800/ 2100 rpm=20 Correction 6000/ 2100 rpm.=20 Bobby=20 Sent from my iPhone On Apr 2, 2019, at 5:46 PM, Bobby J. Hughes bhughes@qnsi.net = wrote: Bill,=20 Most takeoffs have been at 7000/2400 rpm with MP between = 34-38=E2=80=9D to pattern. Climb at 6800/ 2100 rpm=20 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 with F/A 15.8. Or 13.5 for higher MP.=20 Bobby Sent from my iPhone On Apr 2, 2019, at 5:13 PM, William Jepson wrjjrs@gmail.com = 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. The rotary is tough, 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. =20 Bill On Tue, Apr 2, 2019 at 2:02 PM Bobby J. Hughes bhughes@qnsi.net = wrote: My MT weighs 42#=E2=80=99s. The hub 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.=20 Bobby Sent from my iPad On Apr 2, 2019, at 3:48 PM, William Jepson wrjjrs@gmail.com = wrote: Sam,=20 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? 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 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 Jepson On Tue, Apr 2, 2019 at 6:34 AM Samuel Hodges = samueln462wp@att.net wrote: Lately 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 ------=_NextPart_000_022F_01D4EBBA.C961A0D0 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Sam,
Well worth the trip.  Sometimes it amazes me just how stupid = some=20 sales people can be.  You probably dodged a bullet (cost, time to = install,=20 possible problems).
 
Tracy H.
 
 
 
From: Samuel Hodges = samueln462wp@att.net
Sent: Friday, April 5, 2019 8:47 AM
Subject: [FlyRotary] Re: Electric constant speed=20 props
 
Went=20 to Sun n Fun and talked to a Aeromaster representative to collect = information=20 and data on their Electric constant speed prop combinations. After = waiting a=20 little while a representative of the company approached as asked what he = can do=20 for me. I replied that I am extremely interested in their design and = would like=20 further information. I was asked about my aircraft engine installation, = I=20 explained to him about the Rotary and what my RPM requirements would be. = His=20 response went something like this " Do you know how much this cost? it = will=20 probably double the cost of your installation/plane" I immediately took = this as=20 an insult and replied " you know nothing of me, my finances, nor my = plane" as I=20 walked past him I padded him on the arm and said " keep your freakin = prop, you=20 just saved me a lot of money" but I didn't say freakin. One thing I did = find out=20 is that it would be around 26lbs, well worth the trip, wouldn't you = agree?
 
Sam    =20
 
On Tuesday, April 2, 2019, 07:27:12 PM EDT, Bobby J. Hughes=20 bhughes@qnsi.net <flyrotary@lancaironline.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.ne= t>=20 wrote:

Bill,=20
 
Most takeoffs have been at 7000/2400 rpm with MP between = 34-38=E2=80=9D to=20 pattern.
Climb at 6800/ 2100 rpm
 
Cruise at 5200/ 1824 or 4800/ 1624 rpm depending on my desired = fuel burn=20 and airspeed.  Most cross country flight are at 28-30=E2=80=9D MP = and with F/A=20 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.ne= t>=20 wrote:

Bobby, You push it fairly hard with your supercharged = engine=20 too. What cruise RPM are you running? P.Sport always tried to tune = for lower=20 RPMS and higher power to avoid the torsional vibration problems. = With boost=20 you can make more power at lower RPMs which is a plus in this = case. =20 The rotary is tough, the engine will tolerate a lot, but the high = revs for=20 long periods is what causes the need for attention to torsionals. = BTW I=20 moved and had to take a break from my redrive efforts, but am = getting back=20 to it. Got some good ideas today from Mark Hatch, Everett's = son. =20
Bill
 
On Tue, Apr 2, 2019 = at 2:02 PM=20 Bobby J. Hughes bhughes@qnsi.net <flyrotary@lancaironline.ne= t>=20 wrote:
 
My MT weighs 42#=E2=80=99s. The hub is heavy, blades are = light weigh. Gear=20 lashing appears to have increased a little over the first 500 = hours. End=20 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.ne= t>=20 wrote:

Sam,=20
I am working with some originators of Powersport.=20 The weight of your build makes a big difference on the use of a = constant=20 speed. Also in the case of the rotary the quality of your = muffler! Sound=20 levels really effect your comfort on longer flights. Mufflers = for=20 rotaries are tough, I already have 1 failed design to my (bad) = credit.=20 The original Powersport=20 designs used the light weight and flexibility of a wood prop to = their=20 advantage. Those engines were tuned for max power at 6500 RPM. = The=20 reductions were about 1.85 to 2.2:1. suitable for the lower = power peak.=20 Torsional vibration issues also favored a wood prop. How heavy = is the=20 electric Airmaster?=20 MOST engines including the rotary are helped by a variable pitch = prop.=20 Whether the combination is safe depends on the reduction drive, = ratio,=20 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).=20 Their later stiff model internal ring gear reduction gearbox put = the=20 resonances out of the normal range for the rotary. Prior to that = the=20 only problem free build with a planetary was when they built a = pendulous=20 damper system (like a big radial engine uses) which worked great = but was=20 so expensive they figured they would never sell an engine. So if = you are=20 running a planetary reduction you need to keep the weight down = as much=20 as you can. Find out what the Airmaster=20 weighs. The amount that it exceeds your wood or carbon fixed = blade prop=20 is your risk factor. The advantage is to use a low cruise rpm = that takes=20 advantage of the props flexibility. As a thrust producing device = it is=20 better, there is no doubt. If it is very heavy though it may = cause=20 problems that aren't obvious as to origin. Torsional problems = may take=20 hundreds of hours to develop, or something may break the first = week.=20 Just be wary. Always keep track of things like changes in output = shaft=20 end play and backlash. You can make the change, and see = excellent=20 results but go in with your eyes open. Lots of people will tell = you this=20 is nervous nelly stuff, but the guys at P.S. probably had more = hours=20 running and testing rotaries AT HIGH OUTPUT levels than anyone = other=20 than Mazda.
Bill Jepson
=
 
On Tue, Apr 2, = 2019 at 6:34=20 AM Samuel Hodges samueln462wp@att.net = <flyrotary@lancaironline.ne= t>=20 wrote:
Lately I have been considering an Airmaster electric = constant=20 speed prop to help achieve the rotaries true potential. I am = asking=20 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=20 =
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