dkkim73 Posted August 27, 2024 Report Posted August 27, 2024 On 8/26/2024 at 11:04 PM, Shadrach said: I built an aircraft specific spreadsheet long ago that calculates stall and approach speeds in all configurations at any weight and bank angle up to 60°. I was actually curious about the weight range of his aircraft for normal single pilot ops. Normal single pilot ops for me is is between 2000 and 2100lbs (200lb pilot, two hours of fuel remaining and 20 to 40lbs of stuff/baggage). Under those conditions, I’m crossing the threshold of 55kias. If @dkkim73 is crossing the fence at 70kias, I’m guessing he weighs around 2700lbs for that target speed. Expand Heavier than I want, but less than 2700 lbs unless you are including the plane!!! Seriously, though, I probably don't like to operate with much below 24-30 gals in the tank, so call it 2800 at lowest weights. On commutes, I may be landing close to 3200lbs (MLDW) when tankering fuel. I keep it closer to 75 heavy and 70 light. Once within a few feet of the runway, it's comfortable to slow down a lot more. Generally don't go below 80KIAS while maneuvering or reconfiguring. A "designated min. maneuvering speed" (1.4Vs) would seem to be 75-90KIAS based on configuration. So 80-85 until established on final, then trying to slow and stabilize, adjust angle as required. 55KIAS sounds really slow until in ground effect. 1 1 Quote
exM20K Posted August 27, 2024 Report Posted August 27, 2024 On 8/26/2024 at 11:04 PM, Shadrach said: I built an aircraft specific spreadsheet long ago that calculates stall and approach speeds in all configurations at any weight and bank angle up to 60°. I was actually curious about the weight range of his aircraft for normal single pilot ops. Normal single pilot ops for me is is between 2000 and 2100lbs (200lb pilot, two hours of fuel remaining and 20 to 40lbs of stuff/baggage). Under those conditions, I’m crossing the threshold of 55kias. If @dkkim73 is crossing the fence at 70kias, I’m guessing he weighs around 2700lbs for that target speed. Expand A 2700# Acclaim with a 200# pilot has a few cups of fuel. 70 KIAS is fine 2900-3000# in good conditions. -dan 1 Quote
Shadrach Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 12:48 AM, Hank said: Huh??? Expand Stall strips hasten the stall in the area where they are installed by causing boundary layer separation aft of the strip. It causes a consistent localized stall ahead of the break and a pronounced buffet. Quote
Shadrach Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 12:50 AM, dkkim73 said: Heavier than I want, but less than 2700 lbs unless you are including the plane!!! Seriously, though, I probably don't like to operate with much below 24-30 gals in the tank, so call it 2800 at lowest weights. On commutes, I may be landing close to 3200lbs (MLDW) when tankering fuel. I keep it closer to 75 heavy and 70 light. Once within a few feet of the runway, it's comfortable to slow down a lot more. Generally don't go below 80KIAS while maneuvering or reconfiguring. A "designated min. maneuvering speed" (1.4Vs) would seem to be 75-90KIAS based on configuration. So 80-85 until established on final, then trying to slow and stabilize, adjust angle as required. 55KIAS sounds really slow until in ground effect. Expand Same basic airframe with very different wing loading and fuel burn. Thats why I figured you at 2700ish. 20 gals is 2 hours of fuel at cruise for me, so pretty conservative reserves for the end of an XC flight 55kias is slow for the pattern but not for the threshold. I want to be at 1.2xVso over the numbers. At 2000lbs, calculated Vso is ~46kts (less in ground effect). 2 1 Quote
Pinecone Posted August 27, 2024 Report Posted August 27, 2024 The main purpose of stalls strips are to cause that part of the wing to stall first. They are typically inboard to make sure the root area stalls first for a more stable stall. The buffet comes from the stall, whether there are stall strips or not. The original configuration of the Piper Tomahawk had only outboard stalls strips. It has a bit of a lively stall and spin entry. The spin entry was pretty much a 1/2 snap roll then the nose dropped as it continued to roll and become a spin. Piper did add inboard stall strips to make it a bit more docile. I did my CFI spin endorsement in an outboard only stall strip Tomahawk. GREAT fun. Quote
Shadrach Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 2:19 AM, Pinecone said: The main purpose of stalls strips are to cause that part of the wing to stall first. They are typically inboard to make sure the root area stalls first for a more stable stall. The buffet comes from the stall, whether there are stall strips or not. The original configuration of the Piper Tomahawk had only outboard stalls strips. It has a bit of a lively stall and spin entry. The spin entry was pretty much a 1/2 snap roll then the nose dropped as it continued to roll and become a spin. Piper did add inboard stall strips to make it a bit more docile. I did my CFI spin endorsement in an outboard only stall strip Tomahawk. GREAT fun. Expand A stall will always cause a buffet. A stall strip will cause buffet that occurs further ahead of the break. I’ve never removed a strip to see the difference in the buffet. I’m simply relaying what I’ve read how they work and what they do. Quote
Fly Boomer Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 12:48 AM, Hank said: Huh??? Expand "I was under the impression that most GA aircraft had stall strips. Stall strips yield a pronounced buffet before the wing breaks." If you select the text, you can read it. 1 Quote
A64Pilot Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 12:48 AM, Hank said: Old Mooneys have small rudder, stopping the horizontal stabilizer. Around 1965 or 66 or so, the rudder was pushed all the way to the bottom of the vertical stabilizer. So not exactly a "more modern nose wheel airplane. " Expand Smaller, shorter, lighter airplanes with less HP. As they got bigger and especially longer and more power they needed more rudder I’m sure to pass Certification and as they could go down it was most logical as opposed to increasing cord. Going down also increases rudder authority with less roll imparted, and often you need the roll to pass Cert as one requirement is that you must be able to lift a dropped wing with rudder only. To pass that is very often why more modern aircraft often have aileron / rudder interconnects. ”Old” design aircraft were designed to and expected to be spun, spinning back in the day was considered to be a normal thing for smaller single engine airplanes. It wasn’t until later that spins were to be avoided and that trend has continued until we have reached the point where airplanes if a spin is inadvertently entered may not be recoverable, so we need parachutes to get an equal level of safety You may not, but I consider a Mooney a modern design, heck most even consider a Bonanza a modern design and it first flew in 1946 I think? I’ve not measured my little 140’s rudder area but think it has as much as my Mooney, and the little 140 has a half ton less Gross weight and at 85 HP well less than half the HP. Old school would often be prior to WWII and or soon after. Sadly believe it or not but there hasn’t been much advancement in small aircraft design, we literally fly our Grandfathers aircraft. Even the most modern aircraft like say a Cirrus really isn’t in truth very advanced, for whatever reason we never did adopt designs like Routan’s etc. 1 Quote
Pinecone Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 12:43 PM, Shadrach said: A stall will always cause a buffet. A stall strip will cause buffet that occurs further ahead of the brake. I’ve never removed a strip to see the difference in the buffet. I’m simply relaying what I’ve read how they work and what they do. Expand The stall strip causes the flow to trip and have a localized area of the wing stalled at a LOWER AOA than without the strip. Yes, a stall causes a buffet, but there are airplanes where the stall occurs at an AOA below that of the buffet. NOT normal GA aircraft. Quote
varlajo Posted August 27, 2024 Report Posted August 27, 2024 (edited) On 8/26/2024 at 11:04 PM, Shadrach said: I built an aircraft specific spreadsheet long ago that calculates stall and approach speeds in all configurations at any weight and bank angle up to 60°. I was actually curious about the weight range of his aircraft for normal single pilot ops. Normal single pilot ops for me is is between 2000 and 2100lbs (200lb pilot, two hours of fuel remaining and 20 to 40lbs of stuff/baggage). Under those conditions, I’m crossing the threshold of 55kias. If @dkkim73 is crossing the fence at 70kias, I’m guessing he weighs around 2700lbs for that target speed. Expand Yep, same here, for my 71E (in mph) Edited August 27, 2024 by varlajo 1 Quote
Shadrach Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 2:18 PM, varlajo said: Yep, same here, for my 71E (in mph) Expand Nice. Mine is a bit more crude but I just uploaded the latest version. 1 Quote
Shadrach Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 12:48 PM, Fly Boomer said: "I was under the impression that most GA aircraft had stall strips. Stall strips yield a pronounced buffet before the wing breaks." If you select the text, you can read it. Expand Is my post not readable? Quote
Shadrach Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 2:13 PM, Pinecone said: The stall strip causes the flow to trip and have a localized area of the wing stalled at a higher AOA than without the strip. Yes, a stall causes a buffet, but there are airplanes where the stall occurs at an AOA below that of the buffet. NOT normal GA aircraft. Expand I think you meant lower. Quote
Hank Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 3:00 PM, Shadrach said: Is my post not readable? Expand No, it's just three solid black lines. Quote
Shadrach Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 4:23 PM, Hank said: No, it's just three solid black lines. Expand Weird. I saw this happen to half of one of @MikeOH's posts. It looks like it's a dark vs light mode thing... It looks perfectly normal in dark mode. Quote
MikeOH Posted August 27, 2024 Report Posted August 27, 2024 @Shadrach Right you are! I went to 'dark mode' and your post showed up with no problem. I use an iPad; no idea if that has any bearing on the issue but many other people don't seem to have a problem. Did you use any special formatting on that post? Quote
Shadrach Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 5:05 PM, MikeOH said: @Shadrach Right you are! I went to 'dark mode' and your post showed up with no problem. I use an iPad; no idea if that has any bearing on the issue but many other people don't seem to have a problem. Did you use any special formatting on that post? Expand No. In fact, I go out of my way to remove formatting because it's annoying when I try to read posts that are mis-formatted. Whenever I paste, I get a prompt that says: Pasted as rich text. Paste as plain text instead I always chose plain. Quote
MikeOH Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 5:19 PM, Shadrach said: No. In fact, I go out of my way to remove formatting because it's annoying when I try to read posts that are mis-formatted. Whenever I paste, I get a prompt that says: Pasted as rich text. Paste as plain text instead I always chose plain. Expand Interesting. I never get that prompt when I paste. Quote
Shadrach Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 5:36 PM, MikeOH said: Interesting. I never get that prompt when I paste. Expand Looks like this: 1 Quote
Pinecone Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 3:03 PM, Shadrach said: I think you meant lower. Expand Oops. Fixed Quote
Shadrach Posted August 27, 2024 Report Posted August 27, 2024 On 8/27/2024 at 7:20 PM, Pinecone said: Oops. Fixed Expand I’m here to read what you say and ensure that you say what you mean… at least you know someone is paying attention. Quote
Pinecone Posted August 28, 2024 Report Posted August 28, 2024 On 8/27/2024 at 7:34 PM, Shadrach said: I’m here to read what you say and ensure that you say what you mean… at least you know, someone is paying attention. Expand Thank you for that. Quote
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