Adequate Visual Reference?

?

In reference to what? The ability to descend to 100ft Above TDZE?

Need to kinda know where you're going with this.
 
If you are talking about on an approach, then 91.175 provides the list of things required to descend.

(i) The approach light system, except that the pilot may not descend below 100 feet above the touchdown zone elevation using the approach lights as a reference unless the red terminating bars or the red side row bars are also distinctly visible and identifiable.
(ii) The threshold.
(iii) The threshold markings.
(iv) The threshold lights.
(v) The runway end identifier lights.
(vi) The visual approach slope indicator.
(vii) The touchdown zone or touchdown zone markings.
(viii) The touchdown zone lights.
(ix) The runway or runway markings.
(x) The runway lights.
Click to expand...
 
Yes I was referring to takeoff mins, AVR applys when RVR is not adequate to my understanding and is simply enough reference to maintain directional control or is there more?
 
"When certain types of visibility reports are unavailable or specific equipment is out of service, the flight can still depart the airport if the pilot can maintain adequate visual reference. An appropriate visual aid must be available to ensure the takeoff surface can be continuously identified and directional control can be maintained throughout the takeoff run.

Appropriate visual aids include high intensity runway lights, runway centerline lights, runway centerline markings, or other runway lighting and markings. A visibility of RVR 1600 or 1/4 SM is below standard and may be considered adequate for specific commercial operators if contained in an OpsSpecs approval."

(quoted from the Instrument Procedures handbook)

For example, at my company, we are approved for 600 RVR takeoffs. We must have the "adequate visual references" to do so.
 
aviationizhere said:
Yes I was referring to takeoff mins, AVR applys when RVR is not adequate to my understanding and is simply enough reference to maintain directional control or is there more?
Click to expand...

Yes, but what determines adequate visual references is not left completely to your discretion. Here's my prep material on that:

[FONT=Arial, sans-serif]Adequate Visual References[/FONT]​



[FONT=Arial, sans-serif]For someone flying "commercially" (i.e. IAW Title 14 CFR parts 121 or 135), their takeoff minimums and visual reference requirements are contained in Paragraphs C056 and C078 of their Operations Specifications.[/FONT]


[FONT=Arial, sans-serif]For any operation in which the visibility is less than 1/2 mile (Standard Takeoff Minimums are 1/2 mile) Paragraph C078 (IFR Lower Than Standard Takeoff Minimums) contains the relevant operating Standards, Conditions, and Limitations including "visual reference" requirements. Visual references, in general, include various lighting arrangements and centerline markings[/FONT][FONT=Arial, sans-serif].[/FONT]


[FONT=Arial, sans-serif]Here is the relevant text from C078:[/FONT]


[FONT=Arial, sans-serif]C078. IFR Lower Than Standard Takeoff Minimums, 14 CFR Part 121 Airplane Operations - All Airports[/FONT]



[FONT=Arial, sans-serif]a. Runway visual range (RVR) reports, when available for a particular runway, shall be used for all takeoff operations on that runway. All takeoff operations, based on RVR, must use the RVR reports from the locations along the runway specified in this paragraph.[/FONT]


[FONT=Arial, sans-serif][FONT=Arial, sans-serif]b. [/FONT][FONT=Arial, sans-serif]When takeoff minimums are equal to or less than the applicable standard takeoff minimum, the certificate holder is authorized to use the lower than standard takeoff minimums described below:[/FONT][/FONT]


[FONT=Arial, sans-serif](1) Visibility or runway visual value (RVV) ¼ statute mile or touchdown zone RVR 1600, provided at least one of the following visual aids is available. The touchdown zone RVR report, if available, is controlling. The mid RVR report may be substituted for the touchdown zone RVR report if the touchdown zone RVR report is not available.[/FONT]
[FONT=Arial, sans-serif](a) Operative high intensity runway lights (HIRL).[/FONT]
[FONT=Arial, sans-serif](b) Operative runway centerline lights (CL).[/FONT]
[FONT=Arial, sans-serif](c) Serviceable runway centerline marking (RCLM).[/FONT]
  1. [FONT=Arial, sans-serif]In circumstances when none of the above visual aids are available, visibility or RVV ¼ statute mile may still be used, provided other runway markings or runway lighting provide pilots with adequate visual reference to continuously identify the takeoff surface and maintain directional control throughout the takeoff run.[/FONT]
[FONT=Arial, sans-serif]Almost any runway markings will work. CL lights, CL marking, runway edge lights, etc. A snow covered runway without visible lighting wouldn't qualify. When you go below the 1/4mi/RVR1600 level you needs specific lighting and/or markings which are listed right there in the Jepps.[/FONT]


[FONT=Arial, sans-serif](2) [/FONT][FONT=Arial, sans-serif]Touchdown zone RVR 1000 (beginning of takeoff run) and rollout RVR 1000, provided all of the following visual aids and RVR equipment are available.[/FONT]
[FONT=Arial, sans-serif](a) Operative runway centerline lights (CL).[/FONT]
[FONT=Arial, sans-serif](b) Two operative RVR reporting systems serving the runway to be used, both of which are required and controlling. A mid-RVR report may be substituted for either a touchdown zone RVR report if a touchdown zone report is not available or a rollout RVR report if a rollout RVR report is not available.[/FONT]


[FONT=Arial, sans-serif](3) [/FONT][FONT=Arial, sans-serif]Touchdown zone RVR 500 (beginning of takeoff run), mid RVR 500, and rollout RVR 500, provided all of the following visual aids and RVR equipment are available.[/FONT]
[FONT=Arial, sans-serif](a) Operative runway centerline lights (CL).[/FONT]
[FONT=Arial, sans-serif](b) Runway centerline markings (RCLM).[/FONT]
[FONT=Arial, sans-serif](c) Operative touchdown zone and rollout RVR reporting systems serving the runway to be used, both of which are controlling, or three RVR reporting systems serving the runway to be used, all of which are controlling. However, if one of the three RVR reporting systems has failed, a takeoff is authorized, provided the remaining two RVR values are at or above the appropriate takeoff minimum as listed in this subparagraph.[/FONT]

  1. [FONT=Arial, sans-serif]At foreign airports which have runway lighting systems equivalent to U.S. standards, takeoff is authorized with a reported touchdown zone RVR of 150 meters, mid RVR of 150 meters, and rollout RVR of 150 meters. At those airports where it has been determined that the runway lighting system is not equivalent to U.S. standards, the minimums in subparagraphs b(1) or (2), as appropriate, apply.[/FONT]
 
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