---------------------------------------------------------- Rocket-List Digest Archive --- Total Messages Posted Thu 09/22/05: 5 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 08:00 AM - Re: Vx Vy Best glide (Jim Stone) 2. 09:28 AM - Empenage fairing (Bryan Carr) 3. 11:29 AM - Re: Vx Vy Best glide (Hr2pilot@aol.com) 4. 12:48 PM - Re: HRList... Vx Vy, placards...more? (JOHNTMEY@aol.com) 5. 05:34 PM - Re:Performance and Cert (JOHNTMEY@aol.com) ________________________________ Message 1 _____________________________________ Time: 08:00:44 AM PST US From: "Jim Stone" Subject: Re: Rocket-List: Vx Vy Best glide --> Rocket-List message posted by: "Jim Stone" Good post Les! ----- Original Message ----- From: Subject: Re: Rocket-List: Vx Vy Best glide > --> Rocket-List message posted by: Morocketman@aol.com > > An excellent question. And an excellent explanation can be found on my > local "Missouri Pilots Association" web site written by our own Larry > Harmon. > See mopilots.org/sgf/jan2001sgf2.htm. Larry describes the generic values > for > Vx, Vy, and Best Glide speeds, and these are fine for the Rocket. I just > add > the caveat that the Rocket has such an abundance of power that Vx is > really > on the edge should the Lycoming get quiet. It is generally agreed (by > most > test pilots) that Vx is/or about Vs + 20%. Commonly expressed as 1.2 x > Vs. In > my Harmon (no relation to Larry) Rocket II, Vs is about 55 to 56 knots > depending on who is counting. Computing Vx of 66 knots at full takeoff > thrust > would give a body angle that would be very, very dramatic. Assuming > something > came undone, it would require a very rapid pitch over to maintain some > semblance of control near/above the desired Va approach speed (Vs + 30% > or 1.3 Vs > or 73 knots which is the perfect over-the fence feel airspeed). It is > simply > not necessary. My airplane climbs like a "rocket should" at 1.4 x Vs or > 78 > to 80 knots. Now, to address a very different > subject......................... Vy. Oh what a strange, and vague speed > that is, and how do we find it? > Technically, Vy should be 1.4 Vs, again the 78 knot number which > coincidentally > should also be best glide speed. My explanation is that we are much like > a > Century Series jet fighter...........they simply forgot to put enough > "wing > on the thing." An RV-? wing of any kind is a short span, dare I say > chubby > cord, and thick wing. When we clipped our RV-4 wings to the Rocket > length, we > knew we were going the wrong way for gliding. Just look at the high > performance sailplanes with their extremely high aspect ratio "straight > razor" > looking wings. My RV-4 felt-about-right at 85 knots for Vy, and my Rocket > is a > whole lot more like 100 knots. If I lost the engine on the Rocket, and > was > able to get it to course pitch, I would think a great deal about 90 to > 100 knots > until the last three hundred feet. And only then would I reduce to the > desired 73 knots IAS. I know the other factors like weight, wind gusts, > density > altitude, etc., but these are just guidelines from my own very humble > opinion > and 700+ hours on the stubby RV wings. Ya'll be careful out there, and > mainly fly the airplane where you (and it) feel comfortable. Les > Featherston > "Airgasm" 228 hours, and just lovin' it! > > > ________________________________ Message 2 _____________________________________ Time: 09:28:43 AM PST US From: "Bryan Carr" Subject: Rocket-List: Empenage fairing --> Rocket-List message posted by: "Bryan Carr" What is the best fitting empennage fairing for the Harmon Rocket 2? I hate fiberglassing. Bryan Carr ________________________________ Message 3 _____________________________________ Time: 11:29:02 AM PST US From: Hr2pilot@aol.com Subject: Re: Rocket-List: Vx Vy Best glide --> Rocket-List message posted by: Hr2pilot@aol.com VX 90 MPH VY 125 MPH VSO 58 MPH VSI 64 MPH VA 164 MPH ________________________________ Message 4 _____________________________________ Time: 12:48:34 PM PST US From: JOHNTMEY@aol.com Subject: Rocket-List: Re: HRList... Vx Vy, placards...more? --> Rocket-List message posted by: JOHNTMEY@aol.com Listers....good thread recently. Mine's about flight ready. I'm trying to nail down some things for my brain to rehearse before 1st flight. Also making a rudimentary Airplane Flight Manual. Making placards too. 1. John (or others), what is the fuel capacity with bigger tanks ? 2. Anyone know the unusable fuel value ? 3. Insurance. I know the general protocol on insurance ... just wondering what the current rates and rules are ? Who is a good agent? I can show reasonable currency and tailwheel recency in Cubs, Champs, Luscombe, PT22. 4. What is the customary, assigned local flight time limit assigned by the DAR ? 5. When you'all are looking at landing your beauty at a boondock destination, paved airstrip, what is the shortest, narrowist strip you would consider ? Maybe that's a hard question to put numbers upon... how about same question relative to the usually quoted landing distance over a 50' obstacle, zero wind, moderate braking.? Many thanks for any replies. John Meyers HRII N5800 sn 233 do not archive ________________________________ Message 5 _____________________________________ Time: 05:34:54 PM PST US From: JOHNTMEY@aol.com Subject: Rocket-List: Re:Performance and Cert --> Rocket-List message posted by: JOHNTMEY@aol.com Wow, good information. I weigh about 150 and should have a middleweight airframe. Home airstrip is 1600' paved with 500' solid grassy smooth runout. Paved about 35' wide and has 80' trees at one end. I won't try landing there until well-practiced. Wheel landings are my favorite mode. Complex is current. Guess I will see what the insurers say. Can one get any coverage in the flight test phase ? My engine is re-built as a C4B5 but is undoc-ed and logless. Guess that's experimental. Let's see... 40 hours at 15 gph x $10/gallon equals... gulp * John Meyers do not archive