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Questions for all of you wiz-kids

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Active member
Nov 27, 2001
Ok guys,

I'm curious about the following questions. Perhaps you can help me out.

1. How long is a TAF valid?

2. If you flew an ILS glideslope all the way down, how much RW would remain for rollout?

3. Assume FAR part 121. We've passed the final approach fix and tower reports the visibility below minimums. Now what?

4. What are the circling distances for each class?

5. What exactly IS "MSA" on an approach chart. If you go miss, tower instructs you to climb to 4000 and you lose radios, but MSA is 6000, what is the problem?

6. Can you do LAHSO at night?

7. What is the final approach fix on an ILS? What is its significance?

8. Part 121. What equipment is required for takeoff RVR 600/600/600? What does the Jepp have to say?

And last but not least...

9. A B767 takes off in front of you. Tower says you're cleared for an immediate. The captain pulls out the CB on the CVR and says, "we're going. forget the 2 minute wait". What do you do?

Just a few questions to get the wheels spinning again. Its been a long time.

-Yet another furloughed guy
Just answering from what I can remember, don't have references here with me so correct me if I'm wrong.
1. TAF is valid for 24 hours or the prescribed period in the first line.
2. ILS is supposed to put your TDP 1000' down the runway.
3. Dunno
4. Good way to remember circling radii is 3,5,7,23,45:
Cat A: 1.3 B: 1.5 C: 1.7 D: 2.3 E: 4.5
5. Minimum Sector Altitude provides at least 1000' of obstacle clearance within 25 nm of the navigational station in question and is broken up into sectors of 90 deg or more. If you are nordo, below MSA on a vector, you will want to climb to ensure that you don't fly into the obstacle in that sector.
6. Yes.
7. FAF on ILS is GS intercept. Significance is that you have to be configured and established by FAF.
8. Dunno
9. I don't think that the wait is mandatory, but it is definitely prudent. I'd tell him that we're going to wait. I've flown through the wake of another Herc on short final. Having full aileron input one way and still rolling the other way at about 25 feet is not a good feeling.
Alright, I have not flown since 5 Sep, it's Sunday morning, I'm bleary eyed, I have no pubs to reference, only one cup of coffee so far; so forgive me for any errors (after all I don't have a FO to confer with):

1. Normaly 24 hours. Valid period is listed at the beginning of the TAF.

2. (Jepps) Check the RW data on the backside of the airport diagram, usable RW length remaining is listed for each RW with a precision approach.

3. Continue to DH and then decide.

4. Uh, don't have my AIM right here. 1.3 for class C?

5. Minimum Sector altitide. Will provide 1000' obstacle distance within 25 nm (normally) of fix/navaid upon which MSA is defined.
In your MA example Tracon will provide obstacle clearances based upon their minimum vectoring altitides (MVA). MVA is not depicted. If in question, ask the controller.

6. No, and if you tell me yes I still say NO, I'm not doing it!

7. Once cleared for the approach - point at which you intercept the glideslop or glideslope intercept altitude depicted on the approach plate, whichever is higher (answered without the benefit of pub to reference). Significance? reference question #3

8. At least 2 operational transiometers, HIRL, CL & if I had any pubs (or an FO) I'd check for what else. Jepps tell you if other than standard TO minimums are allowed and what they are for each RW.

9. Say "I don't think so." Push the CB back in and transmit to the tower: "Unable." Or, any other combination of verbage and actions that convince the A*****e that he's out to lunch.
Seems like all were answered fairly well- I can expand slight ly on #3 and 8
3. once inside the faf and tower reports below minimums: can continue to dh and land provided
a) have required FLIGHT visibility-- and it is quite often that at a big airport like jfk or dfw that what the pilot encounters is very different than what the tower is reporting 2 miles away. Even with RVR I have seen vast discrepancies
b) continuously in a pos to make landing in TDZ using normal descents and procedures...
c)at least one of following in sight..approach lights.. can go down to 100 feet above TDZ elev unless you have red terminating bar(alsf-1) or red side row bar(alsf-2) which qualify you to continue to land
reil, vasi , threshold, th marking , th lights, tdz, tdzmarkings, tdz lighting, runway ( double check but everything but centerline lights included--which makes since as I have mistaken this for ry edge lights in poor vis.
d)Whatever variants op specs add

600 rvr appears to be in the changing .. our op specs permit 500,500, 500 and this is reflected in part 121.. I have seen some airports for example MIA that are showing this change already.

all 3 rvr must be reporting ( although one may be inop)

To elaborate on FAF on an ILS...

By the very definition of a FAF, if an approach has a final approach segment, it must have a FAF (it simply means the point at which the final approach segment begins).

Referencing the intro section in the Jepps, p.5, "Final Approach Fix (FAF)"....

"The fix from which the final approach (IFR) to an airport is executed and which identifies the beginning of the final approach segment. It is designated in the profile view of Jeppesen Terminal charts by the maltese Cross symbol for nonprecision approaches and by the glide slope/path intercept point on precision approaches. The glide slope/path symbol starts at the FAF. When ATC directs a lower-than-published Glide Slope/Path Intercept Altitude, it is the resultant actual point of the glide slope/path intercept."

In other words, an ILS FAF is at GS intercept, if you intercept it at or below published altitude. If ATC has you on final way out and you happen to intercept the GS at a higher than published altitude, that is not the FAF; you have to ride the GS down to the published intercept altitude to get to the FAF.

Here's a question one of the sim instructors at Cherry Point loves to ask: On a procedure turn approach where the station is located at the field, where is the FAF?

Below is from the AIM Pilot/Ctlr Glossary:
FINAL APPROACH FIX- The fix from which the final approach (IFR) to an airport is executed and which identifies the beginning of the final approach segment. It is designated on Government charts by the Maltese Cross symbol for nonprecision approaches and the lightning bolt symbol for precision approaches; or when ATC directs a lower-than- published glideslope/path intercept altitude, it is the resultant actual point of the glideslope/path intercept.
Many approaches have no final approach fix. Such approaches may have an initial approach fix at the navaid on which the proceedure is predicated, but have no other fixes for the remainder of the approach.

Many NDB approaches, for example, are typical of this. The final approach segment commences when the proceedur turn is complete and the aircraft is established inbound. However, there is no FAF.

You're right that its not technically a final approach fix. On such approaches where no FAF is depicted, intercepting the inbound course is termed as the final approach point and serves as the FAF.

I appreciate all of the answers so far. (especially the circling distances. great mnemonic aid!)

I have a few more for you guys.

1. Is there any good way that you know of to remember the types of approach lighting systems?

2. What Altitude and Airspeed is a dutch roll most likely to occur?

3. What is a good way to remember the lost comm procedures?

4.What are the FAR 121 requirements for fuel on board (turbojet domestic)

5. What kind of icing can be found in a stratus layer above the freezing level?

6.FAR part 121 - If you've passed the FAF and tower reports the visibility below minimums you should....?

7. Who is responsible for obstacle clearance while on radar vectors?

8. What is the speed limit beyond 12 miles from shore (outside of class E areas)?

Again thanks in advance.
A few answers

3. Always remember the easiest answer, if VMC, stay VMC and land VMC.
For route:
AVEnue F: (in order of precedence)
last Assigned
if on Vectors, to the fix you are being vectored to
last told to Expect
if nothing else, as Filed
For altitude AME, the highest of:
the last assigned
the minimum enroute altitue
the last told to expect (but don't use this alt until the
expected point, ie expect at 10 mins, or expect at XYZ)

5. Stratus, steady winds, smooth air, srime icing...ie rime icing, kinda goofy but it sticks. Cumulus, clear icing.

7. On vectors, the controller is responsible for obs clnc, hence the MVA. He has taken over your navigation.

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