POH Charts: What am I doing wrong?
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Here are two pages out of my Warrior POH. I think maybe you are only looking at one of them.
As katchalpin says 75% means 75% of the rated engine HP. To achieve that as you gain altitude (without a turbo) you need more throttle, and also more RPM.
According to the Engine Performance page of the POH 2400RPM will only get you about 60% power at 6500ft and 0º. At that density altitude you need about 2630rpm to get 75%
According to the "Best Power Cruise Performance" page 60% power should get you about 107KTAS which is pretty close to what you were seeing
EDIT: One more thing I forgot to mention - if you are trying to debug stuff like this the tablet actually shows you your exact TAS so you don't need to try to use the ASI or your ground speed + wind correction to work that out. Obviously IRL you wouldn't have a tablet with your TAS so for realism absolutely the way you worked it out is best
@nickd27 Yeah, that's the kind of chart I was missing. That will help immensely, thank you for posting it. I did look up the leaning procedure again and saw that you're supposed to rich 100 degrees, not 50, so maybe I was cheating myself out of a little power there. EGTs seemed to be on the way lower side of the gauge, though, but that could be because I'm finding out I was underpowered.
@Martyn, I noticed that's not in either the manual or the ODM; I can use this one (or look it up myself), but is there a chance we can get updated manuals for the Pipers that include the power chart?
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@nickd27 Yeah, that's the kind of chart I was missing. That will help immensely, thank you for posting it. I did look up the leaning procedure again and saw that you're supposed to rich 100 degrees, not 50, so maybe I was cheating myself out of a little power there. EGTs seemed to be on the way lower side of the gauge, though, but that could be because I'm finding out I was underpowered.
@Martyn, I noticed that's not in either the manual or the ODM; I can use this one (or look it up myself), but is there a chance we can get updated manuals for the Pipers that include the power chart?
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@martyn The second chart is in the ODM, correct, but the first one that shows RPM settings for 55, 65, and 75% power is not. That's the missing one.
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@Martyn I know this is a very old topic, but I'm in the same boat once again. I know you guys added it at some point in the past, but I recently downloaded the latest version of the Warrior ODM from the support website and that Engine Performance chart is missing again!
I overwrote my old copy, too.
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I'm not personally aware of us having an alternative version of the ODM with different charts; however, I'll ask the question to the team in the morning and get back to you.
Mark - Just Flight
@Mark said in POH Charts: What am I doing wrong?:
I'm not personally aware of us having an alternative version of the ODM with different charts; however, I'll ask the question to the team in the morning and get back to you.
Mark - Just Flight
Thanks Mark! There was only ever the one version, and it was updated not long after I made this topic those few years ago.
However, like I said, I just overwrote my copy with one downloaded direct from the support page since you guys don't package them with the aircraft anymore, and it looks like that version is missing the engine power chart (or maybe it's that ancient version, I know you guys were having caching problems on the website a week or two ago).
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@Mark said in POH Charts: What am I doing wrong?:
I'm not personally aware of us having an alternative version of the ODM with different charts; however, I'll ask the question to the team in the morning and get back to you.
Mark - Just Flight
Thanks Mark! There was only ever the one version, and it was updated not long after I made this topic those few years ago.
However, like I said, I just overwrote my copy with one downloaded direct from the support page since you guys don't package them with the aircraft anymore, and it looks like that version is missing the engine power chart (or maybe it's that ancient version, I know you guys were having caching problems on the website a week or two ago).
@jmarkows The following link has the latest version of the Warrior's ODM manual: https://justflight.sharefile.com/public/share/web-sc028e2b4fafe4c0fbab6d79bb8d9e420
The manual link on the support page will still download the previous version at the moment; however, I'm following that up with our IT team to get it updated on the server.
Mark - Just Flight
