windscreen
Figure 23-5D
THE FLARE ATTIUDE
23.7 THE NON PRECISION APPROACH
The Non-Precision Approach, is any approach which does not have an instrument glide-slope. These are: -
1. ILS localiser only. . .
2. VOR. These approaches may be flown with or without DME 3. ILS back beam.
4. NDB. . . 5. VDF
6. PAR with no glide slope information There are two types of NDB let-downs :-
a. The continuous descent approach to Minimum Descent Altitude (MDA) is usually associated with a DME. On reaching MDA, an immediate Go-Around must be initiated. On a continuous descent approach, MDA should be treated as though it was a Decision Altitude (DA).
b. The descent to Minimum Descent Altitude (MDA) and then to fly level to the Missed Approach Point (MAPt). This is called “Dive & Drive” and is NOT recommended. It is a discredited procedure in terms of ‘Flight Safety’ because it has caused numerous CFIT accidents.
The “Continuous Descent” is the approach that is recommended for all aircraft, since it is much more stable and does not have configuration changes at a very low altitude, which can cause instability just prior to the threshold, i.e. ballooning and a deep landing.
There is no reason why single pilot operations should not fly stabilised continuous descent approaches in preference to dive and drive. It is essential however to prepare a cross-check crib of required height at each 15 second point after passing the FAF or DME distance, all the way to touchdown, for easy reference during the approach.
23.8 THE CONTINUOUS DESCENT NON-PRECISION APPROACH
All aircraft should fly an NDB approach in the same way as an ILS. A continuous 3º descent is planned, by flying the appropriate rate of descent as mentioned previously. (Half the Ground Speed multiplied by 10, or 5 times the Ground Speed). In addition:
1. The beacon identification ‘Morse’ group must be continuously monitored during the approach, in case of failure, which will cause the RMI needle to ‘freeze’ and may not be noticed; also
2. Get established on the inbound QDM as early as possible.
3. Monitor the ADF RMI; this will give rate of closure to the inbound QDM. 4. Make small smooth adjustments once established on the QDM.
5. Lower Gear and flaps at 2 nautical miles from descent point, usually the FAF.
6. Call for and do the landing checks. These need to be out of the way before the descent point, since the non- handling pilot needs to be able to monitor and call out the height versus distance in the descent.
7. At ½ a nautical mile select landing flap, remember that the aircraft will balloon slightly, check the flap and have the checklist put away.
8. Pitch into the descent profile. Since the jet suffers from inertia, it cannot change from level flight to the required rate of descent instantly, so it is recommended that the initial rate of descent be greater than the planned rate of descent. For example, ‘Planned’ ROD = 700 ft/min (½ Ground Speed x 10). Commence initial rate of descent at 1,000 ft/min. By doing this the aircraft will regain the Glide Path, then set the required ROD when back on the Glide Path, (see figure 15-5.)
9. The non-handling pilot should call out the heights and distance thus a. “At 8 miles you should be 2,400 feet”
b. “8 miles, 100 ft high, at 7 miles you should be at 2,100 feet,” etc”
If there is no DME, call the target height at each 15 seconds (See figure 23-8) thus c. “At +15 seconds you are 100 feet high. Aim for 1100 feet at +30 seconds,” d “At + 30 seconds you are 50 feet high. Aim for 900 feet at +45 seconds, etc.”
e. Continue calls all the way to touchdown, particularly at night and when the MDH/A is high.
The non-handling pilot needs to make the calls in a crisp manner and then stay quiet, so that the handling pilot can think and adjust the flight path accordingly.
10. When going visual, particularly in a strong cross wind, the handling pilot must freeze the heading that is being flown. Otherwise the immediate reaction is to roll towards the runway removing all the drift and going onto the down wind side. This will then necessitate an “S” turn to get back onto the centre line. In so doing, there will be a considerable height loss.
11. The visual cues are now all the same as on all previous approaches. 12. Again “Anticipate”.
23.8.1 Initiating Final Descent from an initial platform attitude prior to final descent
During an instrument approach it is best to pass the FAF at no more than the +100 feet tolerance permitted but preferably -0 feet, so as not to erode terrain clearance. When a positive indication of desired progress is confirmed, descent may re-commence: then you need to maintain the intended approach slope, even if this means an initial rate of descent slightly higher than the normal target of about 700 feet/minute, now in the landing configuration.
23.8.2 Non-Precision Approach ‘Clock’ for descent profile progress-control
Enter Target Rate of Descent: 800 feet per minute in lower (ROD) box within circle. Then also enter:
FAF height 1500 feet (Enter in space provided above circle) DA 400 feet (QNH) (enter in upper (DA) box within circle)
Airfield Elevation 200 feet (adjusted for threshold / TDZ elevation if significant)
To maintain a 3° approach slope, use 5 times the ground speed (G/S), or half the Groundspeed x 10. a. So for a groundspeed of 140 kts use 140 x 5 = 700 feet / minute; or
b. ½ G/S x 10 = (140 ÷2) x 10 = 70 x 10 = 700 feet / minute.
Figure 23-6 INITIATION OF FINAL DESCENT
Figure 23-5