Non-Precision Approach - Must you follow the published descent profile?
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Non-Precision Approach - Must you follow the published descent profile?
Hello everyone,
Quick question regarding non-precision approaches, as a discussion came up today specifically with regard to the Saleya for runway 22 in Nice.
I was PF, and I wanted to start the final descent from the 12DME AZR point at about 3-400fpm so as to arrive around the Cap Ferrat MAP just over 2,000ft. This would be some 6-700feet about the circling minima at the missed approach point.
I wanted to do this as 1,500ft at the 5.5DME point is fairly low on the profile considering the manouevring around the bay. I felt that 2,000ft and taking the gear at the 5.5DME point was a fairly conservative plan (A320 family).
Captain disagreed and said that when cleared for the Saleya that implied the level constraints as well, and I should be 1,500feet at 5.5DME, then drop down to 1,000 until on the PAPIs. I felt that this was incorrect as it leaves you fairly low and slow, which isn't really in keeping with the spirit of the noise abatement.
Of course in some fairly marginal weather you want to be at the circling minima at the MAP, and to make life easier I could have just opted for a visual approach, but I was just wondering what everyone's thoughts are? Do you have to fly the approach in line with the DME / Altitude as published, or can you fly as high above the profile as you want as long as you are following the procedure laterally?
The VOR approach onto the southerly runway in Bastia is another example of the top of my head.
Anyway, thanks for your insights.
Quick question regarding non-precision approaches, as a discussion came up today specifically with regard to the Saleya for runway 22 in Nice.
I was PF, and I wanted to start the final descent from the 12DME AZR point at about 3-400fpm so as to arrive around the Cap Ferrat MAP just over 2,000ft. This would be some 6-700feet about the circling minima at the missed approach point.
I wanted to do this as 1,500ft at the 5.5DME point is fairly low on the profile considering the manouevring around the bay. I felt that 2,000ft and taking the gear at the 5.5DME point was a fairly conservative plan (A320 family).
Captain disagreed and said that when cleared for the Saleya that implied the level constraints as well, and I should be 1,500feet at 5.5DME, then drop down to 1,000 until on the PAPIs. I felt that this was incorrect as it leaves you fairly low and slow, which isn't really in keeping with the spirit of the noise abatement.
Of course in some fairly marginal weather you want to be at the circling minima at the MAP, and to make life easier I could have just opted for a visual approach, but I was just wondering what everyone's thoughts are? Do you have to fly the approach in line with the DME / Altitude as published, or can you fly as high above the profile as you want as long as you are following the procedure laterally?
The VOR approach onto the southerly runway in Bastia is another example of the top of my head.
Anyway, thanks for your insights.
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The Final approach plate clearly says "At 1500' " at Selya. The Caution also says "at 1000' " when on the 304 track after Selya. It is clear that the Captain's analysis was correct.
In general, an approach profile includes both lateral and vertical constraints. In some cases the vertical constraints are only minimums, but often they are maximums or mandatory altitudes. Read the approach plates closely to determine which apply at any point on the approach.
In general, an approach profile includes both lateral and vertical constraints. In some cases the vertical constraints are only minimums, but often they are maximums or mandatory altitudes. Read the approach plates closely to determine which apply at any point on the approach.
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You can choose to fly any descent profile you like on an NPA - it's just some have fatal consequences.
Try figuring a CFDA from FAF. It has the advantage of allowing you to continue from the MAPt with reconfiguring if you have visual contact.
Hope you live long enough to read this.
Sir George Cayley
Try figuring a CFDA from FAF. It has the advantage of allowing you to continue from the MAPt with reconfiguring if you have visual contact.
Hope you live long enough to read this.
Sir George Cayley
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Yes - there the Captain was correct. Where I suspect the confusion has perhaps arisen is from knowing of the 'old basic' NPAs where no vertical steps were published and descent from 'platform' to MDA could be commenced at any time once established on the inbound track following a base turn. A procedure dearly loved by the 'dive and drive' bandits.
There may well be very good reasons for the 'at' steps on the charts - ATC separation etc and they should be adhered to. Sometimes, however, you will just see 'not below' altitudes - and obviously they are important for terrain clearance. Since the OP asked "or can you fly as high above the profile as you want as long as you are following the procedure laterally" I would say yes as long as there are no published step points and you are not prejudicing acquiring visual reference at MDA and making a safe landing. If those considerations are kept in mind, your colleague knows what and why, it is not dangerous. However, as most modern aviators know, a planned 'on published profile' descent is the best.
There may well be very good reasons for the 'at' steps on the charts - ATC separation etc and they should be adhered to. Sometimes, however, you will just see 'not below' altitudes - and obviously they are important for terrain clearance. Since the OP asked "or can you fly as high above the profile as you want as long as you are following the procedure laterally" I would say yes as long as there are no published step points and you are not prejudicing acquiring visual reference at MDA and making a safe landing. If those considerations are kept in mind, your colleague knows what and why, it is not dangerous. However, as most modern aviators know, a planned 'on published profile' descent is the best.
