After 3 years I’m here, thanks a lot for this video, I have my Flight Planning official exam in one month and now with this video I have the concepts very clear, thanks again👏🏻
I am an ex Assistant Air Traffic Controller (RAF) . I learned all about QFE QNH etc during my trade training (1969) . I found your instructions both informative and interesting, especially as I some inkling of the subject.
Dear Tom. Thank you SOOOOOOO much for helping and creating these videos. i am a Flight Operation Oficer/ Dispatcher student from Portugal, and you are helping me soooooo much getting ready for my exams!! GNAV also! all your videos are very good!!! thanks so much!! please keep it going!!
Absolutely brilliant! My missus is a genius, and it took her a while to get Altimitery, so I was panicking; however, after watching this video, and I'm not that bright, I got it! That is an excellent explanation. Thanks for making such a great bunch of videos!
Thank you SO much for this series of videos!! It's been unbelievably helpful and I finally am getting correct answers to the questions. I cannot thank you enough!!
Hi tom , you are the best tutor i found based on altimetry. It really helped me alot in understanding about altimetry and the different calculations thank u very much
Thanks god for your lessons very very much recommended to all pilots doing ATPL or just learning .it is a must to come over here and check what do you have . i have gone throw the hole 3 lessons . appreciate your time .
My brother in Christ I’m just a student pilot 😂and I’ve been watching your videos For a while. you are amazing at explaining everything I’m glad I found your channel.
Hi Tom, great tutorials. I have been watching your videos for a week now since I was struggling with the harder GNAV topics. GNAV makes a lot more sense now! Would like to see topics on "Time" from GNAV if you get a chance to work on it. Cheers Marc
Hi Tom, what a superb explanation! As in video nr.3 I was calculating with you but used 30' i.s.o. 27' with the result that the provided answers were much closer to the result using 30 feet. Keep on going!!
Excellent! Thanks for the feedback! It seems some boards may expect you to use different values (also different subjects expect different values too). In my experience of the UK CAA the question told me what value of ft/hPa every single time.
Great video series on Altimetry! I would love to see videos on the more challenging parts of subjects like Principles of Flight (Turning, Stalling etc), CRP 5 things, Radio Nav (VOR, DME etc) Once again great video, Keep it up!
For ATPLQ question 504435, the temp correction is subtracted. Why does this happen and how do you know what altitudes to choose to add/subtract from with the temp correction?
18:00 Example shows again that your method based on Hight above the ground is wrong and 4% method is good approximation to real situation. I showed you example of how it is in previous videos
for the last q i used the regular calculation, just assuming that the pressure measurement was done at sea level, and i got the right answer, was it wrong? so for temperature deviation I calculated 4*15*(-15) which equals to 900 ft.
Thank you very much, Your videos are extremely useful. Would you please add a few more questions based on QFE? Also, For your info: IASA/UKCAA's new LOs, requires all the calculations based on 30ft/1hPa.
Hi thanks for your comment! Time is difficult for me right at this moment but I have plans for more videos. I’m thinking mass and balance next, but what would you like?
I never understand at the end if we need to add or substract the difference between QNH pressure and QNE pressure to find the altitude. How to know ? Thank you
The reason is because the last time he substracted the Pressure Deviation Altitude value (PDA:-540), in AVEXAM : 14597 at 10:19 of the video, he was looking for the True Altitude by having already his Pressure Altitude and he determined the Temperature Correction, he has to find the Indicated Altitude in order to find the True Altitude by applying the TC. Easy way to understand : The main formula for Pressure Deviation Altitude value remains PDA = (QNH - QNE)*27 On any case ! Regarding the question shall we add this value or substract this value to the altitude ? Depends on what we are looking for : The main formula is IA = PA + PDA so From Pressure Altitude to determine Indicated Altitude it’s + From Indicated Altitude to determine Pressure Altitude it’s - PDA = 993 QNH - 1013 QNE * 27 = -20 * 27 = -540. On the case AVEXAM 14597 we have Pressure Altitude then we are on the scenario : From PA to IA it’s + So IA = 15000 + (-540) = 14 460. That’s because he was looking for True Altitude (TA). At the last exercise, the reverse way cames on ! At that time, he has to find the PA (Pressure Altitude at 1013hpa) so all the formula would have the opposite signs. Remember the classic was PIT: PA leads to IA leads to TA Now at the last exercise it’s TIP: TA must lead to IA in order to have the PA So all formula changes to opposite signs. REMEMBER: if TA = IA + TC then IA = TA - TC Sign changed. Same case here the IA = PA + PDA (Pressure Deviation Altitude Value), Then in order to have Pressure altitude PA = IA - PDA and PDA = (1003 - 1013)*27 = -270 So finally, PA = IA - (-270) PA = IA + 270 That’s why he added the Pressure Deviation Altitude value to the Indicated Altitude, just to find the correct PA (Pressure Altitude at QNE) 😉.
Hi Tom in all other cases once QNE was heavier than QNH. I mean QNE 1013 is below QNH 1003 in your diagram you subtracted but in last example you add. Why?
The reason is because the last time he substracted the Pressure Deviation Altitude value (PDA:-540), in AVEXAM : 14597 at 10:19 of the video, he was looking for the True Altitude by having already his Pressure Altitude and he determined the Temperature Correction, he has to find the Indicated Altitude in order to find the True Altitude by applying the TC. Easy way to understand : The main formula for Pressure Deviation Altitude value remains PDA = (QNH - QNE)*27 On any case ! Regarding the question shall we add this value or substract this value to the altitude ? Depends on what we are looking for : The main formula is IA = PA + PDA so From Pressure Altitude to determine Indicated Altitude it’s + From Indicated Altitude to determine Pressure Altitude it’s - PDA = 993 QNH - 1013 QNE * 27 = -20 * 27 = -540. On the case AVEXAM 14597 we have Pressure Altitude then we are on the scenario : From PA to IA it’s + So IA = 15000 + (-540) = 14 460. That’s because he was looking for True Altitude (TA). At the last exercise, the reverse way cames on ! At that time, he has to find the PA (Pressure Altitude at 1013hpa) so all the formula would have the opposite signs. Remember the classic was PIT: PA leads to IA leads to TA Now at the last exercise it’s TIP: TA must lead to IA in order to have the PA So all formula changes to opposite signs. REMEMBER: if TA = IA + TC then IA = TA - TC Sign changed. Same case here the IA = PA + PDA (Pressure Deviation Altitude Value), Then in order to have Pressure altitude PA = IA - PDA and PDA = (1003 - 1013)*27 = -270 So finally, PA = IA - (-270) PA = IA + 270 That’s why he added the Pressure Deviation Altitude value to the Indicated Altitude, just to find the correct PA (Pressure Altitude at QNE) 😉.
Hi Tom. Thanks a lot for these great videos. However, I've been trying to do Avex question nº 6395 using your method and I can't get it right. Would you please try to do it and take a picture of it or something :D? I did it with my own sketch (same one that you taught on the videos) and not the one provided in the question.
The reason is because the last time he substracted the Pressure Deviation Altitude value (PDA:-540), in AVEXAM : 14597 at 10:19 of the video, he was looking for the True Altitude by having already his Pressure Altitude and he determined the Temperature Correction, he has to find the Indicated Altitude in order to find the True Altitude by applying the TC. Easy way to understand : The main formula for Pressure Deviation Altitude value remains PDA = (QNH - QNE)*27 On any case ! Regarding the question shall we add this value or substract this value to the altitude ? Depends on what we are looking for : The main formula is IA = PA + PDA so From Pressure Altitude to determine Indicated Altitude it’s + From Indicated Altitude to determine Pressure Altitude it’s - PDA = 993 QNH - 1013 QNE * 27 = -20 * 27 = -540. On the case AVEXAM 14597 we have Pressure Altitude then we are on the scenario : From PA to IA it’s + So IA = 15000 + (-540) = 14 460. That’s because he was looking for True Altitude (TA). At the last exercise, the reverse way cames on ! At that time, he has to find the PA (Pressure Altitude at 1013hpa) so all the formula would have the opposite signs. Remember the classic was PIT: PA leads to IA leads to TA Now at the last exercise it’s TIP: TA must lead to IA in order to have the PA So all formula changes to opposite signs. REMEMBER: if TA = IA + TC then IA = TA - TC Sign changed. Same case here the IA = PA + PDA (Pressure Deviation Altitude Value), Then in order to have Pressure altitude PA = IA - PDA and PDA = (1003 - 1013)*27 = -270 So finally, PA = IA - (-270) PA = IA + 270 That’s why he added the Pressure Deviation Altitude value to the Indicated Altitude, just to find the correct PA (Pressure Altitude at QNE) 😉.
Great question, sorry I was slow to reply! The temperature correction only takes into account the fact that the air temp between you and the ground may not be actual ISA conditions. The elevation of the ground level doesn’t change based on temperature, which is why we don’t apply the TEC to the entire altitude.
on the second question, temp was 15-(2x15)=-15 then -15 - -30= +15 but the video says -15 I am confused, I think we had to say -30 - -15= -15 thank you so much for the videos.
Question ID: 610485 (BGS) Given: An aircraft is flying at FL100, OAT = ISA - 15? C. The QNH, given by a meteorological station with an elevation of 100 ft below MSL is 1032 hPa.1 hPa = 27 ft Calculate the approximate True Altitude of this aircraft. 10600 ft 9400 ft 11200 ft 9900 ft
Great question! I doubt you’d be able to take them in to your exams Ryan. Really I made them as a tool so you can get comfortable laying out all the information you’re given in the question, and visualise what you’re being asked to do. If the diagram works for you then try to practice drawing it once it feels familiar. Before you know it you won’t need my sheets :)
@@ATPLTips Thanks for the quick reply Tom. I didn't think we would be allowed just thinking of ways i could save a few seconds. Thanks for the videos they are really helping. Especially the Polar Stereographic video that stopped me pulling my hair out.
Mate, better to ask the question now than find out the hard way in your exam. Really glad you’re finding the videos helpful!! I’m rubbish at publicity, but would appreciate it if you could remember my channel if any of your friends need any help :)
Before you start the exam and the timer, you should use a few minutes to write down all the formulas you might need during the exam on the scratch papers that they provide. You can also draw a couple of these diagrams from memory, so you don’t have to spend time on it during the exam if you need them. At least that’s what I’m planning to do! 😊
1st question - Elevation is 100ft below MSL (1013hPa). So, would you not add the 100ft to FL figure to find vertical separation - Height for Temperature correction calculation? If you add 100ft to the Indicated altitude that is 1032 QNH figure, this is indicating that elevation is 100ft below 1032 pressure setting rather than 100ft below 1013 (MSL) ??
After 3 years I’m here, thanks a lot for this video, I have my Flight Planning official exam in one month and now with this video I have the concepts very clear, thanks again👏🏻
I am an ex Assistant Air Traffic Controller (RAF) . I learned all about QFE QNH etc during my trade training (1969) . I found your instructions both informative and interesting, especially as I some inkling of the subject.
Dear Tom. Thank you SOOOOOOO much for helping and creating these videos. i am a Flight Operation Oficer/ Dispatcher student from Portugal, and you are helping me soooooo much getting ready for my exams!! GNAV also! all your videos are very good!!! thanks so much!! please keep it going!!
Absolutely brilliant! My missus is a genius, and it took her a while to get Altimitery, so I was panicking; however, after watching this video, and I'm not that bright, I got it! That is an excellent explanation. Thanks for making such a great bunch of videos!
Give this man an oscar 💪
Don’t do that, just tell other people if you think these videos will help them :)
Thank you SO much for this series of videos!! It's been unbelievably helpful and I finally am getting correct answers to the questions. I cannot thank you enough!!
Very well compiled video series.. You have simplified all of this crap in the most simplest way.. Can't thank you enough.. Amazing!!
You just helped me
I thought that there’s no way to understand this for me.
But you helped me
Thank you.
Had a hard time understanding altimetry but your short series had made it so simple and easy to solve. Couldnt thank you enough
Hi tom , you are the best tutor i found based on altimetry. It really helped me alot in understanding about altimetry and the different calculations thank u very much
That’s great! Glad to hear it!!
“Master piece of teaching “
Great stuff mate. I wish you would do more videos like this for other subjects
Thank you very much for your help. The way how you present these topics is very clear and precise
Thanks god for your lessons very very much recommended to all pilots doing ATPL or just learning .it is a must to come over here and check what do you have .
i have gone throw the hole 3 lessons .
appreciate your time .
Thanks Youssef!!
Another BIG thanks from Spain
Exelent video as always!
Avexam: 23217
ATPL Questions: 616065
- Bristol GS: 610478 -
amazing video...i was stuck with this for sooo long...it's so clear now....thank you
Brilliant! Keep up the good work.
My brother in Christ I’m just a student pilot 😂and I’ve been watching your videos For a while. you are amazing at explaining everything I’m glad I found your channel.
I love u man. Sketching it out works like a charm for me
Great! Pictures always help!
Hi Tom, great tutorials. I have been watching your videos for a week now since I was struggling with the harder GNAV topics. GNAV makes a lot more sense now! Would like to see topics on "Time" from GNAV if you get a chance to work on it.
Cheers
Marc
Hi Marc, thanks for the feedback!! I’ll work that into the plan as soon as I can :)
Hi Tom, what a superb explanation! As in video nr.3 I was calculating with you but used 30' i.s.o. 27' with the result that the provided answers were much closer to the result using 30 feet.
Keep on going!!
Excellent! Thanks for the feedback! It seems some boards may expect you to use different values (also different subjects expect different values too). In my experience of the UK CAA the question told me what value of ft/hPa every single time.
Great video series on Altimetry! I would love to see videos on the more challenging parts of subjects like Principles of Flight (Turning, Stalling etc), CRP 5 things, Radio Nav (VOR, DME etc) Once again great video, Keep it up!
Ok, great thinking. Thanks for the ideas!!
The question at 18:05 is in the BGSbank: ref: 610481.
Great video! Really helpful. If possible please make a video on VOR CDI , TO/FROM questions. Cheers!
Sounds like a plan!
thanks so much this series really helped me a lot you would be great in making ATPL content thanks a lot once again
For ATPLQ question 504435, the temp correction is subtracted. Why does this happen and how do you know what altitudes to choose to add/subtract from with the temp correction?
Just thanks. you are a great teacher. congrats!
Thanks!!
18:00 Example shows again that your method based on Hight above the ground is wrong and 4% method is good approximation to real situation. I showed you example of how it is in previous videos
Hello Tom, very nice videos. Congratulations.
Thanks!!
Great job, thank you! Great sheet😊
I'm definitely passing my CPL Met. Thank you
Let me know how it goes!
Thank you very much for this good explanation!!!
Excellent video, thank you!
for the last q i used the regular calculation, just assuming that the pressure measurement was done at sea level, and i got the right answer, was it wrong?
so for temperature deviation I calculated 4*15*(-15) which equals to 900 ft.
Thank you very much, Your videos are extremely useful. Would you please add a few more questions based on QFE? Also, For your info: IASA/UKCAA's new LOs, requires all the calculations based on 30ft/1hPa.
Very helpful. Thank you
Excellent videos. Very helpful!
Hi, can you please make a video on POF- Lift equation please? Thanks
You're doing the Lord's work, thanks.
Your videos are very helpful. Why don't you make more series about atpl calculation question.
Hi thanks for your comment! Time is difficult for me right at this moment but I have plans for more videos. I’m thinking mass and balance next, but what would you like?
Superb ! Thank you !
Thanks you sir for clear my doubt 😊
Thanks for letting me know it helped!!
Because I’m nice.....or sad, ask my wife 😂 brilliant. Wonderful video btw
I never understand at the end if we need to add or substract the difference between QNH pressure and QNE pressure to find the altitude. How to know ? Thank you
The reason is because the last time he substracted the Pressure Deviation Altitude value (PDA:-540), in AVEXAM : 14597 at 10:19 of the video, he was looking for the True Altitude by having already his Pressure Altitude and he determined the Temperature Correction, he has to find the Indicated Altitude in order to find the True Altitude by applying the TC.
Easy way to understand :
The main formula for Pressure Deviation Altitude value remains PDA = (QNH - QNE)*27 On any case !
Regarding the question shall we add this value or substract this value to the altitude ? Depends on what we are looking for :
The main formula is IA = PA + PDA
so
From Pressure Altitude to determine Indicated Altitude it’s +
From Indicated Altitude to determine Pressure Altitude it’s -
PDA = 993 QNH - 1013 QNE * 27 = -20 * 27 = -540. On the case AVEXAM 14597 we have Pressure Altitude then we are on the scenario : From PA to IA it’s +
So IA = 15000 + (-540) = 14 460.
That’s because he was looking for True Altitude (TA).
At the last exercise, the reverse way cames on ! At that time, he has to find the PA (Pressure Altitude at 1013hpa) so all the formula would have the opposite signs.
Remember the classic was PIT:
PA leads to IA leads to TA
Now at the last exercise it’s TIP:
TA must lead to IA in order to have the PA
So all formula changes to opposite signs.
REMEMBER: if TA = IA + TC then
IA = TA - TC Sign changed.
Same case here the IA = PA + PDA (Pressure Deviation Altitude Value), Then in order to have Pressure altitude
PA = IA - PDA
and
PDA = (1003 - 1013)*27 = -270
So finally,
PA = IA - (-270)
PA = IA + 270
That’s why he added the Pressure Deviation Altitude value to the Indicated Altitude, just to find the correct PA (Pressure Altitude at QNE) 😉.
can't believe this is free
thank you so much
Great job dear 👍
Hi Tom in all other cases once QNE was heavier than QNH. I mean QNE 1013 is below QNH 1003 in your diagram you subtracted but in last example you add. Why?
The reason is because the last time he substracted the Pressure Deviation Altitude value (PDA:-540), in AVEXAM : 14597 at 10:19 of the video, he was looking for the True Altitude by having already his Pressure Altitude and he determined the Temperature Correction, he has to find the Indicated Altitude in order to find the True Altitude by applying the TC.
Easy way to understand :
The main formula for Pressure Deviation Altitude value remains PDA = (QNH - QNE)*27 On any case !
Regarding the question shall we add this value or substract this value to the altitude ? Depends on what we are looking for :
The main formula is IA = PA + PDA
so
From Pressure Altitude to determine Indicated Altitude it’s +
From Indicated Altitude to determine Pressure Altitude it’s -
PDA = 993 QNH - 1013 QNE * 27 = -20 * 27 = -540. On the case AVEXAM 14597 we have Pressure Altitude then we are on the scenario : From PA to IA it’s +
So IA = 15000 + (-540) = 14 460.
That’s because he was looking for True Altitude (TA).
At the last exercise, the reverse way cames on ! At that time, he has to find the PA (Pressure Altitude at 1013hpa) so all the formula would have the opposite signs.
Remember the classic was PIT:
PA leads to IA leads to TA
Now at the last exercise it’s TIP:
TA must lead to IA in order to have the PA
So all formula changes to opposite signs.
REMEMBER: if TA = IA + TC then
IA = TA - TC Sign changed.
Same case here the IA = PA + PDA (Pressure Deviation Altitude Value), Then in order to have Pressure altitude
PA = IA - PDA
and
PDA = (1003 - 1013)*27 = -270
So finally,
PA = IA - (-270)
PA = IA + 270
That’s why he added the Pressure Deviation Altitude value to the Indicated Altitude, just to find the correct PA (Pressure Altitude at QNE) 😉.
Hi Tom. Thanks a lot for these great videos. However, I've been trying to do Avex question nº 6395 using your method and I can't get it right.
Would you please try to do it and take a picture of it or something :D? I did it with my own sketch (same one that you taught on the videos) and not the one provided in the question.
sorry but I don't understand when pu plus or minus on temperature correction or still pressure correction could you please explain me
Why in the last exercise you have to add the difference between QNH and 1013 to the altitude ??? In the last exercise, you subtract it when QNH
The reason is because the last time he substracted the Pressure Deviation Altitude value (PDA:-540), in AVEXAM : 14597 at 10:19 of the video, he was looking for the True Altitude by having already his Pressure Altitude and he determined the Temperature Correction, he has to find the Indicated Altitude in order to find the True Altitude by applying the TC.
Easy way to understand :
The main formula for Pressure Deviation Altitude value remains PDA = (QNH - QNE)*27 On any case !
Regarding the question shall we add this value or substract this value to the altitude ? Depends on what we are looking for :
The main formula is IA = PA + PDA
so
From Pressure Altitude to determine Indicated Altitude it’s +
From Indicated Altitude to determine Pressure Altitude it’s -
PDA = 993 QNH - 1013 QNE * 27 = -20 * 27 = -540. On the case AVEXAM 14597 we have Pressure Altitude then we are on the scenario : From PA to IA it’s +
So IA = 15000 + (-540) = 14 460.
That’s because he was looking for True Altitude (TA).
At the last exercise, the reverse way cames on ! At that time, he has to find the PA (Pressure Altitude at 1013hpa) so all the formula would have the opposite signs.
Remember the classic was PIT:
PA leads to IA leads to TA
Now at the last exercise it’s TIP:
TA must lead to IA in order to have the PA
So all formula changes to opposite signs.
REMEMBER: if TA = IA + TC then
IA = TA - TC Sign changed.
Same case here the IA = PA + PDA (Pressure Deviation Altitude Value), Then in order to have Pressure altitude
PA = IA - PDA
and
PDA = (1003 - 1013)*27 = -270
So finally,
PA = IA - (-270)
PA = IA + 270
That’s why he added the Pressure Deviation Altitude value to the Indicated Altitude, just to find the correct PA (Pressure Altitude at QNE) 😉.
Why is FL=10000' when the QNE is below QNH?.Isn't it that FL is based on QNE and not QNH?Do we disregard the distance between the QNE and QNH?
Why don't we apply temperature error correction while finding the elevation
Great question, sorry I was slow to reply! The temperature correction only takes into account the fact that the air temp between you and the ground may not be actual ISA conditions. The elevation of the ground level doesn’t change based on temperature, which is why we don’t apply the TEC to the entire altitude.
The trick to these types of questions is to draw it out on paper, then solve for each part.
Yeah you’re right, I always find that drawing a picture helps give much better situational awareness of what the questions are asking!!
great job
❤ thanks a lot
Thank you
Thanks❤
on the second question, temp was
15-(2x15)=-15
then
-15 - -30= +15 but the video says -15 I am confused,
I think we had to say -30 - -15= -15
thank you so much for the videos.
Question ID: 610485
(BGS)
Given: An aircraft is flying at FL100, OAT = ISA - 15? C. The QNH, given by a meteorological station with an elevation of 100 ft below MSL is 1032 hPa.1 hPa = 27 ft Calculate the approximate True Altitude of this aircraft.
10600 ft
9400 ft
11200 ft
9900 ft
9900ft
9400
How can I convert 10 hPa into km?
1hPa = aprox. 8m
@@michaelmaly2641 Thank you
Would we be allowed to take those sheets into the exam?
Great question! I doubt you’d be able to take them in to your exams Ryan. Really I made them as a tool so you can get comfortable laying out all the information you’re given in the question, and visualise what you’re being asked to do. If the diagram works for you then try to practice drawing it once it feels familiar. Before you know it you won’t need my sheets :)
@@ATPLTips Thanks for the quick reply Tom. I didn't think we would be allowed just thinking of ways i could save a few seconds. Thanks for the videos they are really helping. Especially the Polar Stereographic video that stopped me pulling my hair out.
Mate, better to ask the question now than find out the hard way in your exam. Really glad you’re finding the videos helpful!! I’m rubbish at publicity, but would appreciate it if you could remember my channel if any of your friends need any help :)
@@ATPLTips Already sent some links to your videos. Sure it will help them too.
Before you start the exam and the timer, you should use a few minutes to write down all the formulas you might need during the exam on the scratch papers that they provide. You can also draw a couple of these diagrams from memory, so you don’t have to spend time on it during the exam if you need them. At least that’s what I’m planning to do! 😊
King
1st question - Elevation is 100ft below MSL (1013hPa). So, would you not add the 100ft to FL figure to find vertical separation - Height for Temperature correction calculation? If you add 100ft to the Indicated altitude that is 1032 QNH figure, this is indicating that elevation is 100ft below 1032 pressure setting rather than 100ft below 1013 (MSL) ??
I'm referring to Aveam 99162/ATPLGS100460
Legendary 💸🫡