Airfield Operating Minima

Question 1

20. How do you know if an aerodrome is approved for use?

Answer 1

Refer to Dispatch Perf Man >Authorised Airfields

Question 2

21. What runways are approved?

Answer 2

Only those listed in Dispatch Perf Man>Performance Data other than in an emergency at the commander’s discretion.

Question 3

22. Which Instrument Approach procedures are approved?

Answer 3

All approaches contained in LIDO are approved UNLESS there is specific info in i) Perf Man ii) Loreto or iii) the approach is prohibited as per OMA 8.22.5.e & OMA 8.23 (e.g. AR APCH/LPV/GLS)

Question 4

23. Under what 3 conditions can you NOT factor a Met Viz to get an RVR?

Answer 4

1) when reported RVR avail 2) for calculating take-off minima 3) to establish approach RVR below 800m. Visibility mins that are quoted in feet or meters are either RVR or CMV. Mins stated in units of km or nm/sm are Met Viz. If RVR is unavailable you can convert Met Viz but NOT the other way around. RVR reporting is required when any required RVR minima is below 800m.

Question 5

24. Required take-off minima are 200m. You are given 200m Met Viz for take-off. Can you depart?

Answer 5

No. 1) you cannot convert a met vis for establishing take-off minima 2) Any take-off below 400m (or landing below 550m) is considered LVP’s. 8.22.3.e requires for operations below 400m the RVR be reported.

Question 6

25. What lights do you need on rwy for a night take-off? Landing?

Answer 6

OMA 8.22.9 Runway edge and runway end lights must be on for all night operations, threshold lights must be on for landing by night. However, 8.22.3.e departure at night: at least runway edge lights and runway end lights; or runway centreline lights and runway end lights. For landing it depends on the facilities type of approach being flown but CAT1 Edge lights, threshold lights and runway end lights.

Question 7

26. When do you need multiple RVR’s for take-off?

Answer 7

When RVR’s are below 200m you require all x3 RVR. Lowest possible for a 777 is 75/75/75 with PVD and 125/125/125 without.

Question 8

27. What RVR(s) do you need for take off and where would you find airfield specific mins?

Answer 8

TDZ (and MP if reported). Below 200m SE as well. Commanders assessment can over-ride TD (4 lights @ 15m spacing 75m/ 7 lights +125m). Lowest possible for 777 > 75/75/75 with PVD and 125/125/125 without. Mins no longer on CARD and must be sourced from LIDO AOI pages.

Question 9

28.Some lights are broken for t/o. How do you know what limits to apply?

Answer 9

OMA 8.22.3.g The minima are determined by what remains. For take-off refer to 8.22.3.e.
For landing refer to OMA 8.22.11 “Effect on Landing Minima Degraded Equipment”.
For landing - Not expected to consult below 1000ft.

Question 10

29. You need RVR 1600m for approach. You are given “RVR >1500m”. What should you do?

Answer 10

Factor the Met Viz using table in OMA 8.22.8 (iii) to arrive at CMV. You may never factor below 800m and also pay attention to annotations on LIDO chart as described in 8.22.8. On LIDO Instrument Approach Charts, RVR/CMV values are generally shown without a limiting letter. Any restriction to RVR and/or visibility will be shown by a limiting letter (R or V), meaning that any given value followed by a letter must not be converted. R is measured RVR; V is visibility which cannot be converted. See LIDO Gen Part 1.9.3.5.5.1 Legend of Approach Minima, 11a and 11b.

Furthermore, a conversion of meteorological visibility to RVR (CMV) is not to be used:

When reported RVR is available; or

For calculating any takeoff minima; or

to establish any required approach and landing RVR minimum less than 800 metres.

Question 11

30. What reported RVR’s are required for descent below 1000ft?

Answer 11

TDZ > mins/ WHEN REPORTED MP mins or 125m / SE if relevant (60kts)

Question 12

31. What RVR/Met Viz are required for a visual approach?

Answer 12

Commander may not conduct a visual approach if the viz is below 5Km (USA 3sm). If established on the extended centre line AND visual with the runway this may be reduced to 800m. The TDZ must be at or above the stated visual approach minima if quoted. If not assume 800m. MP 125m and SE if relevant 125m.

Question 13

32.All the transmissometers are broken. Can you make any sort of an approach?

Answer 13

Reference to ‘downgraded equipment’ 8.22.11 permits ops to Cat 1 DH/DA with no RVR assessment. However operations to CAT2 or below require minimum of 1 RVR. It may be possible to factor Met Viz to arrive at an RVR provided the required RVR mins are greater than 800m. If neither RVR nor Met Viz available you may operate to CAT 1 DA/DH (so effectively RVR of 550m). The proviso of course being the Approach Ban. If RVR or Met Viz were available and indicated that the Viz was below CAT1 minima then by definition the approach could not be continued below 1000ft.

Question 14

33. You need to calculate AOM because there are no figures available. What info is available to enable you to do so?

Answer 14

Check AIS and/or request ATC for any over-riding state mins. Consult LIDO eRM>Rules & Regulations 1.6.8.10. There are tables to assist in determination of appropriate minima. If in doubt consider that most CAT 1 ILS are approx 200’ agl and 550m with FALS (full approach lighting system) and NALS (no approach lighting system) guidance for same DH would be approx 1200m. For a ‘typical’ NPA DH of 500-600ft FALS 1800m and NALS 2400m.

Question 15

You line up for take-off and all the RVR system fails. Can you depart?

Answer 15

No. OMA 8.22.3.a If no met vis or RVR info then take-off should only be commenced if the commander can determine that the visibility along the take-off runway is at or above required minima. Practically speaking you could assess TDZ for yourself and use one other RVR. In USA/Canada in operations below 1600ft a minimum of two RVR is specifically required.

Question 16

With respect to Mpilot some airfields are colour coded as Red but appear in the Performance manual implying they are suitable diversions. Why is this?

Answer 16

The performance manual checks only verify the suitability of the runways, taxiways, approaches and departures for a given type. The criteria for classification as a Secondary airfield in mPilot are slightly more stringent in that they include a check of basic ground handling, hence the reason for the discrepancy. Practically all airfields in Perf Man are at least Secondary with one or two exceptions (airfields required for non-scheduled flights, or for recovering non-ETOPS aircraft). OMA 8.2.3 A RED alternate has LDA sufficient for MLW, Wet and Zero wind HOWEVER an in-flight landing performance check should always be performed.

Question 17

In the USA in the absence of further ATC instructions at what point may you fly your preferred speeds?

Answer 17

In the USA, if cleared for the approach with no further speed instructions then the speed is now yours.

Question 18

In the absence of specific ATC speed control in the USA what are the ‘expectations’ of the US AIP?

Answer 18

OMC Area Brief USA:
Aircraft operating between F280 and 10,000 feet must maintain a minimum of 250 Kts.
Arriving turbojet aircraft operating below 10,000 feet must maintain:
a. A speed not less than 210 knots, except;
b. Within 20 flying miles of the airport of intended landing, a speed not less than 170 knots. AIM 4-4-12.

Question 19

Below what Visibility must you have RVR for take-off? And for landing?

Answer 19

8. 22.3.e - RVR reporting is required for operations at or below 400m
9. 22.8 - RVR reporting is required for approach and landing operations to be conducted with any RVR minima less than 800 metres.

Question 20

Overlay approach. Elaborate?

Answer 20

An ‘overlay’ is just some pink string ‘overlaid’ on the raw approach, whether that’s a LOC, VOR, VOR/DME, ADF etc.

As such, if the raw data isn’t available, we can’t fly the approach (as per OM A).

Here’s a complication: The 777, for example, is certificated to carry out such an approach without the raw data (as per FCTM) BUT we can’t do it, as the OM A is overriding in this case.

In the past, the 777 has been authorised on an overlay on a route where the local navaid was u/s but it required an exemption to do so.

In short, until OM A changes, you need the basic data (e.g. the VOR/DME for a VOR/DME approach).