From: utzoo!decvax!harpo!eagle!mhtsa!alice!rabbit!ark Newsgroups: net.aviation Title: Approach speeds? Article-I.D.: rabbit.1007 Posted: Tue Dec 21 10:24:38 1982 Received: Wed Dec 22 02:05:37 1982 Jeff Williams makes the following statement: First, the approach catigory of an airplane is based on 1.3 Vs0. However, if you are maneuvering at a speed over 90 knots, your Cessna 172 (catigory A - 1.3 Vs0 = ~58 knots) will actually use catigory approach minima. I presume he meant to put a "B" between the first and second words of the last line. At any rate, I believe this statement is only partially correct. Here is my evidence: >From the Pilot/Controller Glossary section of the Jeppesen Airport and Information Directory (their version of the AIM): Aircraft Approach Category -- A grouping of aircraft based on a speed of 1.3 times the stall speed in the landing configuration at maximum gross landing weight. An aircraft shall fit in only one category. If it is necessary to maneuver at speeds in excess of the upper limit of a speed range for a category, the minimums for the next higher category should be used. For example, an aircraft which falls in Category A, but is circling to land at a speed in excess of 91 knots, should use the approach Category B minimums when circling to land. The categories are as follows: A - < 91 knots B - 91 to < 121 knots C - 121 knots to < 141 knots D - 141 to < 166 knots E - 166 knots or more This is a curious paragraph. First it says that a particular airplane is permanently assigned to a single category. Then it says that under certain conditions you should use the miniums appropriate to the next higher category. The conditions are when it is "necessary to maneuver" faster than the upper limit for the category. Is flying an ILS "maneuvering?" This paragraph does not say explicitly, but it refers only to circling as its example. For further elucidation, we turn to the "Arrival--IFR" section: INSTRUMENT APPROACH PROCEDURES a. Minimums are specified for various aircraft approach categories based upon a value 1.3 times the stalling speed of the aircraft in the landing configuration at maximum certificated gross landing weight. (See FAR 97.3(b)) If it is necessary, whilc circling to land, to maneuver at apeeds in excess of the upper limit of the speed range for each category, due to the possibility of extending the circling maneuver beyond the area for which obstruction clearance is provided, the circling minimum for the next higher approach category should be used. For example, an aircraft which falls in category C, but is circling to land at a speed in excess of 145 knots, should use the approach category D minimum when circling to land. This paragraph is more clearly restricted to circlng to land. I have not been able to find any such paragraph to talk about other approach operations. I do not have a copy of FAR 97.3. The argument about using circling minimums for the higher category are well taken, but I wasn't talking about that. My question is this: If I am flying an ILS approach at an indicated airspeed of 95 knots in a 172, do I have to use Category B approach minimums? If the answer is yes, can someone quote me the regulations that apply?