Aircraft/Landing Category

[Northbeach]

Punk666,

To resolve this question it helps me to compartmentalize the answer. By that I mean to think on different levels at the same time.

For certification purposes, with the governmental regulatory having jurisdiction in issuing the legal authority to fly (for me here in the U.S.A. that’s the FAA) an aircraft will only fit into one category. And that is exactly as you stated:

From what I remember to determine which cateogry the A/C falls under its the stall speed at max landing weight in full landing config X 1.3 or in other words St1 X 1.3.

There are certification requirements. The manufacturer says it is a – category based on their criteria. In this regime a specific type of aircraft will usually only fit into one category (for approach).



Your company SOP is an entirely different document than the certification guidelines the aircraft received its type certificate under. For dispatch purposes; if your company wants to go from a category C to a category D (you and I both know this will increase the minimums, requiring higher visibility) and the government regulatory agency signs off on this policy, then you are a category “D” for the given operation-according to your company.

Your airline is free to set it own policy, with the concurrence of the overseeing governmental regulatory body, that policy become your SOP and dispatch operational procedure.


Then there is the practical application. Let’s say your Boeing is certified and operated as a category “C”. But it is a bad day for you as you just took off at maximum weight, lost the engine and had to divert to your takeoff alternate that only has circling minimums published. And when you begin to configure you discover that the flaps are jammed and will not deploy. You are above maximum certified landing weight with a clean wing. What minimums apply, the aircraft was certified as a “C” category? Go to category “D”, based on your actual speed as you will not be able to slow down to the category “C” speeds.

That becomes the practical application on any given day based on system abnormalities.

What category does my jet fit into? That it depends on who is asking the question and what the circumstances are. By certification it is what Boeing/Airbus and the regulatory agency says it is. If my company, with the approval of the government oversight agency says something else, then that is what I will operate it under. If the jet is broke, and I can’t “fit” into the approach speed for the “agreed upon” category then I will use whatever category I need to.

Northbeach (likes flying the Boeing -900)