QFE approach in Almaty..help
Thread Starter
Join Date: Dec 2010
Location: igloo
Posts: 63
Likes: 0
Received 0 Likes
on
0 Posts
QFE approach in Almaty..help
Hi,
I flew into Almaty last week and have a question regarding the altitudes while conducting the approach. The ATIS reported a QFE of 933. Yes, 933...not 993. I triple checked the reading and even asked ATC for confirmation. Of course, I cannot dial my altimeter down to this number.
My equipment is not that sophisticated but it allows me to put my altimeter into metric mode and read meters. I have flown in and out of Moscow several times and I usually put the given QFE in the window and fly the meters requested, i.e. maintain 500 meters. No big deal. I guess this always worked since I was given a QFE that I could dial into my altimeter.
But last week in Almaty really got my attention. The controller asked if I wanted a QFE or QNH approach. I first said QFE...until I realized that I could not simply dial in the 933 setting. So, I then asked for the QNH approach. He gave me a manageable QNH and then told me to descend to a specified number of meters...maybe 600 meters or something. Normally, meters and QNH should not go together...but there was no other choice. I did no conversion and trusted the controller was reading an accurate QNH setting.
Can somebody with some experience in this area please be so kind as to lend some advice? I have read through several posts, but many say to simply put in the QFE and fly the meters requested...fine this works great in Moscow..no prob, but in Almaty it was a different story. A 933 altimeter setting doesn't work.
Thank you
I flew into Almaty last week and have a question regarding the altitudes while conducting the approach. The ATIS reported a QFE of 933. Yes, 933...not 993. I triple checked the reading and even asked ATC for confirmation. Of course, I cannot dial my altimeter down to this number.
My equipment is not that sophisticated but it allows me to put my altimeter into metric mode and read meters. I have flown in and out of Moscow several times and I usually put the given QFE in the window and fly the meters requested, i.e. maintain 500 meters. No big deal. I guess this always worked since I was given a QFE that I could dial into my altimeter.
But last week in Almaty really got my attention. The controller asked if I wanted a QFE or QNH approach. I first said QFE...until I realized that I could not simply dial in the 933 setting. So, I then asked for the QNH approach. He gave me a manageable QNH and then told me to descend to a specified number of meters...maybe 600 meters or something. Normally, meters and QNH should not go together...but there was no other choice. I did no conversion and trusted the controller was reading an accurate QNH setting.
Can somebody with some experience in this area please be so kind as to lend some advice? I have read through several posts, but many say to simply put in the QFE and fly the meters requested...fine this works great in Moscow..no prob, but in Almaty it was a different story. A 933 altimeter setting doesn't work.
Thank you
You can imagine the knob turning when airlines used to go into Mexico City (7316 above MSL) using QFE.
I don't understand why you say meters and QNH don't go together. They work fine together. They're just numbers. You have to make sure you and the controller are using the same system. It's been 6 months since I was last in Almaty but I don't recall anything strange. Jepp charts show the QNH altitudes in feet and QFE in feet and meters. Almaty knows us and just gives us the QNH settings.
I don't understand why you say meters and QNH don't go together. They work fine together. They're just numbers. You have to make sure you and the controller are using the same system. It's been 6 months since I was last in Almaty but I don't recall anything strange. Jepp charts show the QNH altitudes in feet and QFE in feet and meters. Almaty knows us and just gives us the QNH settings.
Join Date: Oct 2000
Location: South West UK
Posts: 367
Likes: 0
Received 0 Likes
on
0 Posts
Don't be descending to 600 Metres on QNH anywhere around Almaty, you'll hit the ground!! Please make sure you know what you are doing before you go flying into these places in IFR
Join Date: Jan 2010
Location: UK
Posts: 302
Likes: 0
Received 0 Likes
on
0 Posts
Hi chimichanga
Have flown into ALA a few times and may be able to offer a little help. As stated ATC will offer you the option of a QFE or QNH approach. We always elect to go for the QNH approach with cross checking of cleared altitude in metres versus altitude in feet via a company generated metric conversion block. The stated QFE you gave of 933Hpa is very low but if you add the threshold elevation millibar correction from the approach plate which I think is 79mb then this gives you a working QNH of 1012. When ATC clear you to, for example, GELKI you are cleared to 1600m on QNH. Off our conversion table this cleared altitude corresponds to 5200ft (the plate gives 5180ft) and then further descent is down to 1300m which is 4300ft. This is all double checked and confirmed by both crew members before descending. We also have a metric conversion pb which is selected on below Transition and can be used to cross check. High terrain, high elevation airfield and high temperatures make this field challenging and when you throw into the mix the weather ( summer BIG cb's and in winter 75m FZFG and temperatures well south of freezing) its not one to be treated lightly. ATC overall do a pretty good job and I've never had any problems.
Hope this is of assistance.
Have flown into ALA a few times and may be able to offer a little help. As stated ATC will offer you the option of a QFE or QNH approach. We always elect to go for the QNH approach with cross checking of cleared altitude in metres versus altitude in feet via a company generated metric conversion block. The stated QFE you gave of 933Hpa is very low but if you add the threshold elevation millibar correction from the approach plate which I think is 79mb then this gives you a working QNH of 1012. When ATC clear you to, for example, GELKI you are cleared to 1600m on QNH. Off our conversion table this cleared altitude corresponds to 5200ft (the plate gives 5180ft) and then further descent is down to 1300m which is 4300ft. This is all double checked and confirmed by both crew members before descending. We also have a metric conversion pb which is selected on below Transition and can be used to cross check. High terrain, high elevation airfield and high temperatures make this field challenging and when you throw into the mix the weather ( summer BIG cb's and in winter 75m FZFG and temperatures well south of freezing) its not one to be treated lightly. ATC overall do a pretty good job and I've never had any problems.
Hope this is of assistance.
Thread Starter
Join Date: Dec 2010
Location: igloo
Posts: 63
Likes: 0
Received 0 Likes
on
0 Posts
I appreciate your analysis.
As stated, I usually select the metric function (in Russia and CIS nations) on my altimeter and put the QFE in the window. I then fly QFE approaches and ATC is giving me descent clearances based on QFE altitudes. For example, Moscow says for me to maintain 500 meters and intercept the localizer from a 90 degree angle...you know the usual.
The issue was that I was unable to put such a low QFE (933) in my altimeter window)...thus when the controller gave me the option of a QNH approach...I took it. The controller in Almaty gave me the QNH of 1012 and told me to descend to 1600m and later on a descent to 1300m...just like you said Dave Clarke Fife.
Dave Clark Fife: Do you think it is OK to keep my altimeter in the meters mode and have a QNH in the window? Or is it better in your opinion to keep the altimeter in its "normal" mode of reading feet with a QNH setting and then see what 1600m and 1300m equates to in feet and then descend to that particualr value with feet shown on the altimeter?
As stated, I usually select the metric function (in Russia and CIS nations) on my altimeter and put the QFE in the window. I then fly QFE approaches and ATC is giving me descent clearances based on QFE altitudes. For example, Moscow says for me to maintain 500 meters and intercept the localizer from a 90 degree angle...you know the usual.
The issue was that I was unable to put such a low QFE (933) in my altimeter window)...thus when the controller gave me the option of a QNH approach...I took it. The controller in Almaty gave me the QNH of 1012 and told me to descend to 1600m and later on a descent to 1300m...just like you said Dave Clarke Fife.
Dave Clark Fife: Do you think it is OK to keep my altimeter in the meters mode and have a QNH in the window? Or is it better in your opinion to keep the altimeter in its "normal" mode of reading feet with a QNH setting and then see what 1600m and 1300m equates to in feet and then descend to that particualr value with feet shown on the altimeter?
Join Date: Jan 2010
Location: UK
Posts: 302
Likes: 0
Received 0 Likes
on
0 Posts
Can't dictate company policy or advise you to change your SOP's chimichanga but if you are used to making QNH approaches in the rest of the world and you are able to cross check and verify the cleared altitude In metres versus feet via a metric conversion block then do it...
Last edited by Dave Clarke Fife; 20th Jun 2012 at 11:44.
