Another Ifr Question...
 

When (da) Is Reached On The Glide Slope, What Visibility Do I Need To Continue With The Approach Before Going Missed?

Taking the easy way out.
 

91.175, I think it is... The visibility prescribed in the approach for your aircraft category, or if you're flying at a higher speed the appropriate category. You will always go below DA/H though, you just can't "continue" below DA/H. Essentially the vis on the bottom of the approach plate, for you probably the Cat. A.

You need to at least have the approach lights in sight in order to continue the approach. If you do not see the "runway environment" (REILs, and at least the first several runway lights) within the next one hundred feet, then you should then go missed.

Don't forget the approach to landing has to be able to be made in a safe manner. Seeing the beacon as you pass over doesn't give you the right to just dump flaps, bank her 90 degrees and bring her in.

Damn it!:mad:

Visibility is that of whatever is on the plate. 91.175 (d)(2)

To descend, you must have one of the following:
-Approach Lighting - allows you to descend to 100 feet ABOVE the TDZE

-Threshold
-Threshold Markings
-Threshold Lights
-REILS
-VASI
-Touchdown zone or Touchdown Zone Markings
-Touchdown zone lights
-Runway or runway markings
-Runway lights

Right, 91.175 outlines three things you need to continue the approach to the runway.

1. you must be able to descend from the DA to the runway using normal maneuvers
2. you must meet the visibility and ceiling minimums prescribed in the IAP.
3. you must be able to visually identify one of the ten things that make up the runway environment

• the touchdown zone
• the touchdown zone markings
• the touchdown zone lights
• runway end identifier lights (REIL)
• VASI
• touchdown zone or touchdown zone markings
• touchdown zone lights
• the runway or runway markings
• the runway lights
• the approach light system - once you have this in sight, you are allowed to descend to 100 feet above the touchdown zone elevation unless the red terminating bars are also visible.

A lot of students have the misconception that only having the ALS will allow you to go 100 feet below the DA.

If you do not meet these three criteria, then you must go missed.

I always thought that if you have the ALS you are able to descend down to 100 above the TZDE? I know that once you're 100 above the TZDE and you don't meet the 3 requirement you have to go missed approach.

Also, you don't have to have the ceiling requirements in order to land. The regs only state that "The flight visibility is not less than the visibility prescribed int he standard istrument appraoch being used" It can be broken at 150 ft, but as long as you have the visibility, runway environment, and normal descent you can continue.

Remember that it is flight visibility not reported ground visibility. The missed approach point on a precision approach is the DH unless you have the ALS in sight as previously stated. You can descend below the DH however it is the point at which you must decide whether to continue the approach or go missed. I teach this in the following way: The DH is like a trapoline in which you either break through or spring up(Missed), where as an MDA is like a brick wall that you cannot penetrate without 3 criteria being met (runway environment in sight, prescribe visibility, continuos position to land)

Didn't I effectively just post this right above you?