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ArnaudC
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Group: Forum Members
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For quick MET readouts I use the AeroWeather app. It calculates DA. Most POHs have a PA/DA conversion chart at the beginning of section 5. Cruise performance charts can be used for it as well. As mentioned by T67M above, unless T/O/climb/LDG performance calculations are made in SD as well, you still have to open your POH. Displaying only the DA without the rest is only semi-useful.
+xWhat you need for them is (generally) pressure altitude, and that's trivial to obtain with no calculation whatsoever (set 1013.25 in the Kohlsmann Windows and read the altimeter). It's easier to set the field elevation and read the PA in the window. Potato potato.
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Daniel Sinn
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+x+xChris, you forgot to say exactly why it would be useful. What exactly do you use the DA number for, once you have it? Density altitude is the critical parameter to calculate the take off distance and the climb rate.
The most dramatic example i know is Samedan LSZA at 5600 ft altitude. Before you are allowed to fly there you must pass an examination in internet. The calculation of the density altitude is an important part of it. The reason for that is that there where to many deadly accidents at take off. To increase the awareness for the density altitude it would be very helpful to get the density altitude in each METAR reported by SkyDemon.
Yes, I am aware the we mountain pilots will probably never get the desired improvement, since we are a minority among the customers of SkyDemon. Very sad situation.
I totally agree
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BearLS
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+xChris, you forgot to say exactly why it would be useful. What exactly do you use the DA number for, once you have it? Density altitude is the critical parameter to calculate the take off distance and the climb rate.
The most dramatic example i know is Samedan LSZA at 5600 ft altitude. Before you are allowed to fly there you must pass an examination in internet. The calculation of the density altitude is an important part of it. The reason for that is that there where to many deadly accidents at take off. To increase the awareness for the density altitude it would be very helpful to get the density altitude in each METAR reported by SkyDemon.
Yes, I am aware the we mountain pilots will probably never get the desired improvement, since we are a minority among the customers of SkyDemon. Very sad situation.
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T67M
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According to most POH, the first step in calculating the takeoff/landing distance is to factor pressure altitude and temperature togheer, effectively "calculating" the density altitude. However, no two POHs then use this in the same way. Since SD (rightly or wrongly) doesn't do the performance calculations for you, there is no point (IMO) in SD calculating a useless number that can't be used in the POH charts/tables for aircraft performance. What you need for them is (generally) pressure altitude, and that's trivial to obtain with no calculation whatsoever (set 1013.25 in the Kohlsmann Windows and read the altimeter).
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Martin Bech
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If you can calculate TOD in different temp and at different altitudes - so can a computer program!!
It is just a matter of giving the program neccesary information to do that. I know there are a person on this forum who do not want more help from SD, but want you to do things manually.......old stuff.
Other systems calculate TOD, so can SD. I would like to have that giving a simple possibility to make the calc before every flight.
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Ralf Rösch
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Initially I thought as well that it is a good idea to have the DA in in SD in order to calculate the TO-Distances. But practically, when looking at the diagramms in the flight-handbooks of the planes I know (Diamond DA40, Piper PA28's, Aquila A210), I did not find a way to calculate (or derive) the TO-Distance with DA as input. So the benefit of having DA in SD appears very limited to me.
But maybe I missed something and have now the opportunity to learn.
BR
Ralf
PS: There is a great app (IOS, Android I do not know) called "AutoDens" which is very handy for that
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Daniel Sinn
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+1
the DA is a must have value for the takeoff-distance. without that you can't fly save on hot days and high/short runways.
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Chris_LSZO
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+xChris, you forgot to say exactly why it would be useful. What exactly do you use the DA number for, once you have it? The DA is a very important value to calculate the takeoff distance...
Chris
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Tim Dawson
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Chris, you forgot to say exactly why it would be useful. What exactly do you use the DA number for, once you have it?
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Chris_LSZO
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+xWe would only implement this if many customers wanted it, so we look forward to seeing how this thread progresses. You may also wish to expand on exactly why the feature is "very useful". Well, here in Switzerland during the last weeks often I has "hot&high" conditions. For example at Samedan LSZS. To calculate the DA is 100% needed and for sure, it will be "very useful", if SD can support the pilots with this.
Chris
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