ragedracer1977 Posted September 14, 2019 Report Posted September 14, 2019 I've owned my Mooney for just about 2.5 years. I've logged 600 hours flying her around. My ASI has a kollsman window, and I would always adjust it for TAS. No matter what, I would always see about 145-155 mph true. That always seemed a little slow to me, but you know, it is what it is. Last week, I had the new Garmin OAT interface installed. This shows TAS on the G5. Wouldn't you know, the G5 displayed the true always thought my plane should be doing. 165ish MPH. So, I figured my mechanical ASI was just off. I mean indicated always matched indicated on the G5, so I guessed the kollsman window just didn't work right. Until today. I don't know why, but I finally figured it out. Did you know the left side of the kollsman window is for temps above 0c and the right side is for temps below 0c? I've been doing it wrong, I guess because in my head, 0c would be in the middle so above would be on the right and below would be on the left.... For almost 3 years, I've been adjusting my ASI to the wrong side. 7 4
rbridges Posted September 14, 2019 Report Posted September 14, 2019 Dang, dude. I think that deserves a 709 ride. j/k 1
ArtVandelay Posted September 14, 2019 Report Posted September 14, 2019 Forget the TAS, your G5 shows 137 IAS, your mechanical shows 119.Tom
Shadrach Posted September 14, 2019 Report Posted September 14, 2019 Just now, ArtVandelay said: Forget the TAS, your G5 shows 137 IAS, your mechanical shows 119. Tom The G5 is in mph just like the outer ring of the ASI.
kpaul Posted September 14, 2019 Report Posted September 14, 2019 1 minute ago, ArtVandelay said: Forget the TAS, your G5 shows 137 IAS, your mechanical shows 119. Tom Looks like the G5 is in MPH which matches pretty closely to the machinal ASI.
ArtVandelay Posted September 14, 2019 Report Posted September 14, 2019 Looks like the G5 is in MPH which matches pretty closely to the machinal ASI. The GS is in knots? I didn’t see the mph. Boy that’s confusing, I would pick one or the other.Tom
Bob_Belville Posted September 14, 2019 Report Posted September 14, 2019 5 minutes ago, ArtVandelay said: The GS is in knots? I didn’t see the mph. Boy that’s confusing, I would pick one or the other. Tom If the G5 installation instructions are like the Aspen, the installer is required to use MPH since that is what the original owners manual uses. (A friendly hangar fairy can change it to KTS if desired.)
ArtVandelay Posted September 14, 2019 Report Posted September 14, 2019 If the G5 installation instructions are like the Aspen, the installer is required to use MPH since that is what the original owners manual uses. (A friendly hangar fairy can change it to KTS if desired.) Wouldn’t that apply to the ground speed as well?Tom
aviatoreb Posted September 14, 2019 Report Posted September 14, 2019 Well I learned a word! kollsman window
MIm20c Posted September 14, 2019 Report Posted September 14, 2019 51 minutes ago, ArtVandelay said: The GS is in knots? I didn’t see the mph. Boy that’s confusing, I would pick one or the other. Tom All the speeds on the G5 are in MPH. The ground speed is showing a 14 mph headwind component.
ragedracer1977 Posted September 14, 2019 Author Report Posted September 14, 2019 36 minutes ago, ArtVandelay said: Wouldn’t that apply to the ground speed as well? Tom GS isn't a required indication. The G5 has to display airspeed in MPH because that's how all the airspeed limitations are set in the owners manual. I could have GS display in mph but I prefer it in knots because all approaches are timed by knots, not MPH
ragedracer1977 Posted September 14, 2019 Author Report Posted September 14, 2019 1 minute ago, MIm20c said: All the speeds on the G5 are in MPH. The ground speed is showing a 14 mph headwind component. No, the ground speed is knots. Says it right there 1
ragedracer1977 Posted September 14, 2019 Author Report Posted September 14, 2019 22 minutes ago, aviatoreb said: Well I learned a word! kollsman window Technically I don't think it's a kollsman window, that's what I my CFI called it because you adjust for barometric pressure. Like the "real" kollsman window on your altimeter. 1
aviatoreb Posted September 14, 2019 Report Posted September 14, 2019 8 minutes ago, ragedracer1977 said: Technically I don't think it's a kollsman window, that's what I my CFI called it because you adjust for barometric pressure. Like the "real" kollsman window on your altimeter. Are you saying you taught me a word incorrectly?!
Ragsf15e Posted September 14, 2019 Report Posted September 14, 2019 10 hours ago, ragedracer1977 said: I've owned my Mooney for just about 2.5 years. I've logged 600 hours flying her around. My ASI has a kollsman window, and I would always adjust it for TAS. No matter what, I would always see about 145-155 mph true. That always seemed a little slow to me, but you know, it is what it is. Last week, I had the new Garmin OAT interface installed. This shows TAS on the G5. Wouldn't you know, the G5 displayed the true always thought my plane should be doing. 165ish MPH. So, I figured my mechanical ASI was just off. I mean indicated always matched indicated on the G5, so I guessed the kollsman window just didn't work right. Until today. I don't know why, but I finally figured it out. Did you know the left side of the kollsman window is for temps above 0c and the right side is for temps below 0c? I've been doing it wrong, I guess because in my head, 0c would be in the middle so above would be on the right and below would be on the left.... For almost 3 years, I've been adjusting my ASI to the wrong side. I’m about to pull the trigger on G5 and was wondering about that TAS indication... did you have to get a new temp probe added under the wing? Is there a new box and connection under the panel? What about winds? Display on the HSI?
ArtVandelay Posted September 14, 2019 Report Posted September 14, 2019 GS isn't a required indication. The G5 has to display airspeed in MPH because that's how all the airspeed limitations are set in the owners manual. I could have GS display in mph but I prefer it in knots because all approaches are timed by knots, not MPH The early Js went through a transition to knots and have both, including AS indicator like yours with both. I assume newer models are in knots only (at least when they stopped using mph top speed as the model number).Tom
ragedracer1977 Posted September 14, 2019 Author Report Posted September 14, 2019 12 minutes ago, Ragsf15e said: I’m about to pull the trigger on G5 and was wondering about that TAS indication... did you have to get a new temp probe added under the wing? Is there a new box and connection under the panel? What about winds? Display on the HSI? It's awesome! Yes, a new probe installed under the wing. Don't buy the Garmin probe. They want like $400 for it. The GAD13 (little control box) is about $140 and a Davtron C307PS probe is about $75. The Davtron probe is called out as acceptable in the installation manual. The GAD13 is tiny. You could fit one in the little pocket on the front of your jeans. I get TAS and OAT displayed on the top G5. The HSI gets wind direction and velocity. You can have it displayed with a little arrow showing direction or displayed as headwind/tailwind-crosswind component. Also, since the airdata is shared with the 430W I also get a wind display on that.
ExpressJetter Posted September 14, 2019 Report Posted September 14, 2019 As far as the GS discussion, I'd want my GS in Knots. Helps with easy calculations on the sectional/ time/distance/fuel calculations. Everything in the world of flying is in Nautical miles when charted. When flying the plane for speeds, use MPH since POH has those in mph. In short I like the GS in Knots and indicated and true in MPH
ragedracer1977 Posted September 14, 2019 Author Report Posted September 14, 2019 18 minutes ago, ExpressJetter said: As far as the GS discussion, I'd want my GS in Knots. Helps with easy calculations on the sectional/ time/distance/fuel calculations. Everything in the world of flying is in Nautical miles when charted. When flying the plane for speeds, use MPH since POH has those in mph. In short I like the GS in Knots and indicated and true in MPH Yup, that's why mine is set up the way it is 1
Shadrach Posted September 14, 2019 Report Posted September 14, 2019 2 hours ago, ArtVandelay said: The early Js went through a transition to knots and have both, including AS indicator like yours with both. I assume newer models are in knots only (at least when they stopped using mph top speed as the model number). Tom My 67F came from the factory with an ASI that read in both (outer MIAS, inner KiAS). The POH is in MPH. I’m not sure if you’re still confused about his markings but the ASI and G5 match up perfectly. 1
Ragsf15e Posted September 14, 2019 Report Posted September 14, 2019 4 hours ago, ragedracer1977 said: It's awesome! Yes, a new probe installed under the wing. Don't buy the Garmin probe. They want like $400 for it. The GAD13 (little control box) is about $140 and a Davtron C307PS probe is about $75. The Davtron probe is called out as acceptable in the installation manual. The GAD13 is tiny. You could fit one in the little pocket on the front of your jeans. I get TAS and OAT displayed on the top G5. The HSI gets wind direction and velocity. You can have it displayed with a little arrow showing direction or displayed as headwind/tailwind-crosswind component. Also, since the airdata is shared with the 430W I also get a wind display on that. Thanks, that’s 100 times more helpful than the literature and manual.
ZuluZulu Posted September 14, 2019 Report Posted September 14, 2019 6 hours ago, ragedracer1977 said: It's awesome! Yes, a new probe installed under the wing. Don't buy the Garmin probe. They want like $400 for it. The GAD13 (little control box) is about $140 and a Davtron C307PS probe is about $75. The Davtron probe is called out as acceptable in the installation manual. The GAD13 is tiny. You could fit one in the little pocket on the front of your jeans. I get TAS and OAT displayed on the top G5. The HSI gets wind direction and velocity. You can have it displayed with a little arrow showing direction or displayed as headwind/tailwind-crosswind component. Also, since the airdata is shared with the 430W I also get a wind display on that. Your VSI must be very confused living its life out in a Mooney... 2
Ned Gravel Posted September 14, 2019 Report Posted September 14, 2019 I found the "kollsman" window discussion interesting. So here is the definitive definition. It is from the interweb, so it must be true.
bonal Posted September 14, 2019 Report Posted September 14, 2019 Has to be the best speed mod I've ever read about.
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