---------------------------------------------------------- TeamGrumman-List Digest Archive --- Total Messages Posted Wed 09/03/08: 5 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:45 AM - Re: Re:cowling update (teamgrumman@aol.com) 2. 05:47 AM - Re: Re:cowling update (flyv35b) 3. 06:02 AM - Re: Re:cowling update (Steve Roberts) 4. 06:08 AM - Re: Re:cowling update (linn Walters) 5. 06:50 AM - Re: Re:cowling update (flyv35b) ________________________________ Message 1 _____________________________________ Time: 12:45:50 AM PST US Subject: Re: TeamGrumman-List: re:cowling update From: teamgrumman@aol.com Climb performance is more of a function of excess horsepower and weight than drag. =C2-At Vy, induced drag is more of a player in overall drag than is parasitic drag. =C2-Induced drag would be more of a function of airfoil d esign than cowling design. The questions should be: =C2- =C2-=C2-(1) do any of the planes climb at book values? =C2-=C2-(2) what prop was used for the book values? =C2-61 inch, 62 in ch, 63 inch, 64, inch or 65 inch pitch? (by-the-way, the POH has climb performance=C2-for various weights, not just gross weight) =C2-=C2-(3) what were the conditions under which the tests were performe d. =C2-i.e.,=C2-were the numbers in the POH =C2-=C2- A. extrapolated from a continuous climb at Vy to various altit udes? B. evaluated for climb rate from a stabilized level flight condition and a maximum airspeed=C2- to a specified altitude then re-stabilizing level flight and repeati ng? =C2-=C2- Why am I surprised? =C2-The only issue should be if I increased the drag o n the cowling then climb performance would come into question. =C2-A more indicative test would be fuel flow at various altitudes and airspeeds. =C2 -A test like this would indicate if the cowling affected the overall drag. =C2- -----Original Message----- From: ski2little@aol.com Sent: Tue, 2 Sep 2008 4:09 am Subject: TeamGrumman-List: re:cowling update Not surprised FAA requires a climb test - presumably to confirm the plane ca n stil l climb at least as well as stock plane - at gross weight.=C2- I'm more su rprised this was a surprise. Get the MapQuest Toolbar. Directions, Traffic, Gas Prices & More! ________________________________ Message 2 _____________________________________ Time: 05:47:40 AM PST US From: "flyv35b" Subject: Re: TeamGrumman-List: re:cowling update I think where the ball got dropped is that the FAA should have outlined and specified what tests were required at the beginning of the program. Not d one it piecemeal and at the last minute said =22oh, by the way, you need to d o a climb test=22! Although they can do this, it isn't the way they are supp osed to handle these STC programs. You should have been notified about thi s test requirement a long time ago and the test could have been incorporate d with the cooling climb test. Cliff ----- Original Message ----- From: teamgrumman@aol.com To: teamgrumman-list@matronics.com Sent: Wednesday, September 03, 2008 12:43 AM Subject: Re: TeamGrumman-List: re:cowling update Climb performance is more of a function of excess horsepower and weight t han drag. At Vy, induced drag is more of a player in overall drag than is parasitic drag. Induced drag would be more of a function of airfoil design than cowling design. The questions should be: (1) do any of the planes climb at book values=3F (2) what prop was used for the book values=3F 61 inch, 62 inch, 63 inch, 64, inch or 65 inch pitch=3F (by-the-way, the POH has climb performance for various weights, not just gross weight) (3) what were the conditions under which the tests were performed. i.e ., were the numbers in the POH A. extrapolated from a continuous climb at Vy to various altitudes=3F B. evaluated for climb rate from a stabilized level flight condition and a maximum airspeed to a specified altitude then re-stabilizing level flight and repeating=3F Why am I surprised=3F The only issue should be if I increased the drag on the cowling then climb performance would come into question. A more indica tive test would be fuel flow at various altitudes and airspeeds. A test li ke this would indicate if the cowling affe cted the overall drag. -----Original Message----- From: ski2little@aol.com To: teamgrumman-list@matronics.com Sent: Tue, 2 Sep 2008 4:09 am Subject: TeamGrumman-List: re:cowling update Not surprised FAA requires a climb test - presumably to confirm the plane can still climb at least as well as stock plane - at gross weight. I'm mo re surprised this was a surprise. --------------------------------------------------------------------------- --- Get the MapQuest Toolbar. Directions, Traffic, Gas Prices & More! or=3FTeamGrumman-List=22>http://www.matronics.com/Navigator=3FTeamGrumman-List ================ ================== p://forums.matronics.com ution=22>http://www.matronics.com/contribution --------------------------------------------------------------------------- --- Get the MapQuest Toolbar. Directions, Traffic, Gas Prices & More! =5F-=========================================================== =5F-= - The TeamGrumman-List Email Forum - =5F-= Use the Matronics List Features Navigator to browse =5F-= the many List utilities such as List Un/Subscription, =5F-= Archive Search & Download, 7-Day Browse, Chat, FAQ, =5F-= Photoshare, and much much more: =5F-= --> http://www.matronics.com/Navigator=3FTeamGrumman-List =5F-=========================================================== =5F-= - MATRONICS WEB FORUMS - =5F-= Same great content also available via the Web Forums! =5F-= --> http://forums.matronics.com =5F-=========================================================== =5F-= - List Contribution Web Site - =5F-= Thank you for your generous support! =5F-= -Matt Dralle, List Admin. =5F-= --> http://www.matronics.com/contribution =5F-=========================================================== --------------------------------------------------------------------------- --- Checked by AVG. 7:19 AM -- ________________________________ Message 3 _____________________________________ Time: 06:02:27 AM PST US From: "Steve Roberts" Subject: Re: TeamGrumman-List: re:cowling update Hey Cliff we are talking about the government remember... LOL We shall not cease from exploration. And at the end of all our exploring Will be to arrive were we started And know the place for the first time - T. S. Eliot Steve Roberts - AA-1B N641HY @ ILG ----Original Message Follows---- From: "flyv35b" Subject: Re: TeamGrumman-List: re:cowling update I think where the ball got dropped is that the FAA should have outlined and specified what tests were required at the beginning of the program. Not done it piecemeal and at the last minute said "oh, by the way, you need to do a climb test"! Although they can do this, it isn't the way they are supposed to handle these STC programs. You should have been notified about this test requirement a long time ago and the test could have been incorporated with the cooling climb test. Cliff ----- Original Message ----- From: teamgrumman@aol.com To: teamgrumman-list@matronics.com Sent: Wednesday, September 03, 2008 12:43 AM Subject: Re: TeamGrumman-List: re:cowling update Climb performance is more of a function of excess horsepower and weight than drag. At Vy, induced drag is more of a player in overall drag than is parasitic drag. Induced drag would be more of a function of airfoil design than cowling design. The questions should be: (1) do any of the planes climb at book values? (2) what prop was used for the book values? 61 inch, 62 inch, 63 inch, 64, inch or 65 inch pitch? (by-the-way, the POH has climb performance for various weights, not just gross weight) (3) what were the conditions under which the tests were performed. i.e., were the numbers in the POH A. extrapolated from a continuous climb at Vy to various altitudes? B. evaluated for climb rate from a stabilized level flight condition and a maximum airspeed to a specified altitude then re-stabilizing level flight and repeating? Why am I surprised? The only issue should be if I increased the drag on the cowling then climb performance would come into question. A more indicative test would be fuel flow at various altitudes and airspeeds. A test like this would indicate if the cowling affe cted the overall drag. -----Original Message----- From: ski2little@aol.com To: teamgrumman-list@matronics.com Sent: Tue, 2 Sep 2008 4:09 am Subject: TeamGrumman-List: re:cowling update Not surprised FAA requires a climb test - presumably to confirm the plane can still climb at least as well as stock plane - at gross weight. I'm more surprised this was a surprise. ------------------------------------------------------------------------------ Get the MapQuest Toolbar. Directions, Traffic, Gas Prices & More! or?TeamGrumman-List">http://www.matronics.com/Navigator?TeamGrumman-List ================ ================== p://forums.matronics.com ution">http://www.matronics.com/contribution ------------------------------------------------------------------------------ Get the MapQuest Toolbar. Directions, Traffic, Gas Prices & More! ------------------------------------------------------------------------------ Checked by AVG. 7:19 AM -- ________________________________ Message 4 _____________________________________ Time: 06:08:54 AM PST US From: linn Walters Subject: Re: TeamGrumman-List: re:cowling update Years ago I was TDY in San Louis Obispo and attended an EAA chapter meeting. The speaker used the numbers in a Piper owners manual to show how using the numbers in certain situations could ruin your whole day. It turns out that he was one of Bedes test pilots on the AA-1. I think that test methods used way back when probably aren't applicable to todays environment. But that observation comes from limited exposure to the FAA as I can. :-) Linn teamgrumman@aol.com wrote: > Climb performance is more of a function of excess horsepower and > weight than drag. At Vy, induced drag is more of a player in overall > drag than is parasitic drag. Induced drag would be more of a function > of airfoil design than cowling design. > > The questions should be: > (1) do any of the planes climb at book values? > (2) what prop was used for the book values? 61 inch, 62 inch, 63 > inch, 64, inch or 65 inch pitch? > (by-the-way, the POH has climb performance for various weights, not > just gross weight) > (3) what were the conditions under which the tests were performed. > i.e., were the numbers in the POH > A. extrapolated from a continuous climb at Vy to various altitudes? > B. evaluated for climb rate from a stabilized level flight condition > and a maximum airspeed > to a specified altitude then re-stabilizing level flight and repeating? > > Why am I surprised? The only issue should be if I increased the drag > on the cowling then climb performance would come into question. A > more indicative test would be fuel flow at various altitudes and > airspeeds. A test like this would indicate if the cowling affe cted > the overall drag. ________________________________ Message 5 _____________________________________ Time: 06:50:19 AM PST US From: "flyv35b" Subject: Re: TeamGrumman-List: re:cowling update I can tell you one thing: If you believe the takeoff distance (ground roll and over a 50 ft obstacle) performance numbers in an AA-1XX POH for higher density altitude takeoffs you are in for a rude awakening unless you leave LOTS of reserve. Cliff ----- Original Message ----- From: "linn Walters" Sent: Wednesday, September 03, 2008 6:07 AM Subject: Re: TeamGrumman-List: re:cowling update > > > Years ago I was TDY in San Louis Obispo and attended an EAA chapter > meeting. The speaker used the numbers in a Piper owners manual to show > how using the numbers in certain situations could ruin your whole day. It > turns out that he was one of Bedes test pilots on the AA-1. I think that > test methods used way back when probably aren't applicable to todays > environment. But that observation comes from limited exposure to the FAA > as I can. :-) > Linn > > > teamgrumman@aol.com wrote: >> Climb performance is more of a function of excess horsepower and weight >> than drag. At Vy, induced drag is more of a player in overall drag than >> is parasitic drag. Induced drag would be more of a function of airfoil >> design than cowling design. >> >> The questions should be: (1) do any of the planes climb at book values? >> (2) what prop was used for the book values? 61 inch, 62 inch, 63 inch, >> 64, inch or 65 inch pitch? >> (by-the-way, the POH has climb performance for various weights, not just >> gross weight) >> (3) what were the conditions under which the tests were performed. >> i.e., were the numbers in the POH >> A. extrapolated from a continuous climb at Vy to various altitudes? >> B. evaluated for climb rate from a stabilized level flight condition and >> a maximum airspeed to a specified altitude then re-stabilizing level >> flight and repeating? >> Why am I surprised? The only issue should be if I increased the drag >> on the cowling then climb performance would come into question. A more >> indicative test would be fuel flow at various altitudes and airspeeds. A >> test like this would indicate if the cowling affe cted the overall drag. > > > -- > Date: 9/1/2008 7:19 AM > > -- ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message teamgrumman-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/TeamGrumman-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/teamgrumman-list Browse Digests http://www.matronics.com/digest/teamgrumman-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.