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Please explain Cat I and Cat II terms

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I don't care what you you fly. I gave the reference, so read it.

7-3-9. Air Traffic Wake Turbulence Separations

a. Because of the possible effects of wake turbulence, controllers are required to apply no less than specified minimum separation for aircraft operating behind a heavy jet and, in certain instances, behind large nonheavy aircraft (i.e., B757 aircraft).

1. Separation is applied to aircraft operating directly behind a heavy/B757 jet at the same altitude or less than 1,000 feet below:

(a) Heavy jet behind heavy jet-4 miles.

(b) Large/heavy behind B757 - 4 miles.

(c) Small behind B757 - 5 miles.

(d) Small/large aircraft behind heavy jet - 5 miles.

2. Also, separation, measured at the time the preceding aircraft is over the landing threshold, is provided to small aircraft:

(a) Small aircraft landing behind heavy jet - 6 miles.

(b) Small aircraft landing behind B757 - 5 miles.

(c) Small aircraft landing behind large aircraft- 4 miles.

REFERENCE-
Pilot/Controller Glossary Term- Aircraft Classes.

3. Additionally, appropriate time or distance intervals are provided to departing aircraft:

(a) Two minutes or the appropriate 4 or 5 mile radar separation when takeoff behind a heavy/B757 jet will be:

(1) From the same threshold.

(2) On a crossing runway and projected flight paths will cross.

(3) From the threshold of a parallel runway when staggered ahead of that of the adjacent runway by less than 500 feet and when the runways are separated by less than 2,500 feet.

NOTE-
Controllers may not reduce or waive these intervals.

b. A 3-minute interval will be provided when a small aircraft will takeoff:

1. From an intersection on the same runway (same or opposite direction) behind a departing large aircraft,

2. In the opposite direction on the same runway behind a large aircraft takeoff or low/missed approach.

NOTE-
This 3-minute interval may be waived upon specific pilot request.

c. A 3-minute interval will be provided for all aircraft taking off when the operations are as described in subparagraph b1 and 2 above, the preceding aircraft is a heavy/B757 jet, and the operations are on either the same runway or parallel runways separated by less than 2,500 feet. Controllers may not reduce or waive this interval.

d. Pilots may request additional separation i.e., 2 minutes instead of 4 or 5 miles for wake turbulence avoidance. This request should be made as soon as practical on ground control and at least before taxiing onto the runway.

NOTE-
14 CFR Section 91.3(a) states: "The pilot-in-command of an aircraft is directly responsible for and is the final authority as to the operation of that aircraft."

e. Controllers may anticipate separation and need not withhold a takeoff clearance for an aircraft departing behind a large/heavy aircraft if there is reasonable assurance the required separation will exist when the departing aircraft starts takeoff roll.
 
CVSFLY, thanks for the reference. I did not realize that the separation was based on when you're crossing the threshold. That makes sense to me now. Seems like every time I've been "rocked" by a 75 is when a controller gave me an early turn into the approach, followed by "slow to final approach speed." In essence turning me when I'm only 4 miles in trail of the 75, but slowing me so that I would have 5 miles by the time I crossed the threshold.
 
CVSFly,

I read your post, and the AIM section, you are right. Which then caused me to wonder why in certain cases this is not applied. I should say more than certain cases. I see it violated alot. I will pay closer attention to it now to see. So I did some research.

I did find a bulletin called ANTICIPATED SEPERATION at

www.faa.gov/ATPubs/ATB/atbhme.HTM

It is under the above named title. dated 00-6 FALL 2000

All I can figure from this is that it is not being followed and maybe they need to be called on it.
 
Back to the terminology here. I recently got confussed with the terms. Specifically, applying for a Customs overflight permit according to the 19 CFR 122.25 (c)(2) item speaks of listing a class of aircraft and another operators example suggests that it refers to a weight class (I, II, III, etc).

Terms as I understand right now: Class of aircraft in regards to FAR 1.1 and 61 for certification of airman means SEL, MEL, SES, helicopter, airship, etc and for certification of aircraft means airplane, rotorcraft, balloon, etc. Class in regards to a weight division, perhaps as used in ICAO terms - ???? Category in regards to 1.1 and 61 for certification of airman means airplane, rotorcraft, lighter-than-air, etc. and for certification of aircraft means normal, utility, transport, etc. Also for 1.1 it speaks of Category A and B talks to transport category rotorcraft and Part 97 refers to Cat A, B, C, D, & E for approach category of aircraft based on 1.3 Vso. Then in 1.1 and part 91 we come to Cat I, II, III, IIIa, IIIb, & IIIc for ILS minimums. Then its aircraft classes for the purposes of wake turbulance separation (Pilot/Controller Glossary) heavy, large, and small (ICAO uses light, medium, heavy ?). Then large aircraft for aircraft over 12,500 lbs for aircraft cerification and type rating requirements. I feel like Abbott and Costello with who's on first! Anyway, maybe this helps or maybe more confused. Anyone have any other references for Class or Category pertaining to aircraft? Especially in regards to a weight class and 122.25?
 
CVSFly,

No worries, If I can learn something new everyday it is a good day. I should have read what you wrote before assuming how things are done out-on the line. I am sure you and I could probably write a book on infractions that take place in the system everyday on the pilot and controller sides.

AAflyer:)
 
I don't think anyone has really touched on CAT IIIc approaches. As far as I know, the FAA has not approved them, so you won't find them in the U.S. They are done at some airports in Europe. It is an autoland procedure, and there are NO MINIMUMS. You can do a landing and never see the runway on CAT IIIc.
 

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