IMC Tracking and ILS

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Rush, Rush, Rush

This evening’s flight was a bit of a rush. I managed to leave work on time and got to the club shortly after 6pm, to find Roger was in the air with his previous student and looked to be running a little late. I took the time to check the wind, note down the ATIS and calculate headings with the whizz wheel in preparation for ADF tracking and an ILS approach.

The weather had looked a little daunting – dark clouds brought a rain shower through – but this had cleared before the time of my flight and the sun shone through.

With Roger in an upbeat mood, he asked me to book out and preflight the aircraft while he debriefed his previous student. We’d be flying in SNUZ again, which had had the major electrical failure on Monday, but was now back in service. The session was primarily to sort out my ADF tracking problems demonstrated on Tuesday. I’d spent time re-reading the theory book and practicing the ILS approach on the RANT simulator the previous evening.

With me having completed the checks, he hopped in and I radioed for startup clearance after which we promptly taxied off (remembering to check brakes, compass/DI/Turning/Balance Ball/ADF), completed power checks and were cleared for departure.

Strong Sunshine

As we lined up (and I remembered to take a minute to double check the compass and DI aligned with the runway), the sun was shining strongly directly ahead. There isn’t a sun visor in this aircraft, so as we took off I found it difficult to see the instruments. I had to hold one hand over my brow to see them – something very unlikely to be needed in cloud. It wasn’t suitable to put sunglasses on, so instead Roger lent me his cap which helped but took a little while to sort out. We climbed to 1600 feet in the standard SID departure (with the wind from 260, there was little drift to compensate for), then turned North to depart the zone. I then requested permission to turn North West in order to intercept the 300 radial and climb to 4000 feet. Roger had me climbing whilst making the intercept which I broadly managed to do, turning onto a 30 degree intercept path until we reached it. I had calculated that we needed only a few degrees of drift correction, which I applied and we tracked this outbound to 10 miles.

Roger then asked me what the correct quadrantial level should be. With a heading between 271 and 360, I said I thought this should be “even + 500”, i.e. 4500 feet. He asked me to fly the quadrantial level and made me feel that I’d got this wrong somehow. I had thought I had the quadrantial rule correct, but was now doubting it. After a while, he pointed out that I was still on QFE and should by now be on the standard pressure setting 1013.2. When we departed the zone, I had been fiddling about with the cap and not handled the radio call which included reminding us of the regional pressure setting – so missed changing that on the altimeter. A schoolboy error perhaps, and hopefully would have been picked up with a FREDA check. I’ll also need to revise my theory about when to change to standard pressure setting again. The transition level at Lyneham is 3500 feet (or FL35). We’d used the QNH on the previous flight at this altitude and I thought that was the case again today – perhaps I had misunderstood the requirement to climb to 4000 feet actually meant FL40. In either case, I need to revise this theory again so I am absolutely confident about it.

Roger also prompted me to lean the mixture at this height, something that I’d only ever done a couple of time before (when he was instructing me a couple of months earlier).

Procedure Turn

Having tracked outbound successfully (albeit at the wrong altitude), Roger then asked me to turn back to the beacon. We had completely different ideas of what was being asked for here. I still had it in my mind that I needed to do a “teardrop” turn, similar to entering a hold, where you turn through about 315 degrees and then make a 45 degree intercept with the reciprocal heading. What Roger actually wanted was a 45 degree turn away, fly for a minute, then 180 degree rate 1 turn and fly back to intercept.

So naturally he was surprised to see such a completely different set of tracking and stepped in to set the heading bug and give clear instructions of the headings and turns to make.

Tracking back to the beacon

We then headed back to the airfield for the NDB to ILS approach procedure. On my previous flight, I’d completely got this wrong so had just re-read up on the difference between homing (bad) and tracking (good) towards a beacon. So I found it amusing to be asked to home to the beacon (when of course we should be tracking to it). Helpfully, tracking towards it at 120 would allow us to be within the required +/- 30 degree reciprocal bearing, so we could then depart directly onto the correct outbound track.

This worked well, and I saw the ADF rotate as we passed overhead with the DME confirming our proximity. Radioed that we were Lima Alpha beacon outbound and that QFE was set (which is now was), and we were cleared for the NDB/ILS approach.

ILS Approach

The tracking outbound went OK and I performed the cockpit checks. Being unused to leaning the mixture, I overlooked that it was still leaned (despite saying the mnemonic) and had to have this pointed out to me. Turned onto North at the 8 mile mark on the DME and planned to stay on that heading for about 15 seconds before turning onto the intercept course and ensure I wasn’t turning too tightly. This wasn’t what Roger had expected, but when I explained how and why another instructor had taught me this, he was happy with that technique.

At this point I should have switched the DME to the ILS frequency (it was still on the TACAN which is located about 1 mile further in), but overlooked it.

Turning to intercept the ILS, it was helpful to have practised this on the simulator. I could see the ADF turning and that gave me more confidence that I hadn’t overshot and when to expect it to register. On earlier approaches during my training, I had completely overlooked how helpful the ADF is for situational awareness as you approach the localiser and would let you know if you had overshot or would completely undershoot. As the localiser started to move, I turned onto the approach track and was relieved to see we were still below the glideslope at the correct height. It should have been easy to follow the ILS down from that point, but for some reason I didn’t track it particularly well. I was flying a little fast,  and while Roger was encouraging me to concentrate on getting the glideslope right I flew off to the side beyond the 1/2 scale deflection that is the test standard. I did recover though and had the crosshairs pretty much on centre as we descended to Decision Height, at which point the foggles came off and the runway was clearly visible.

Low level circuit

With other traffic around, we made a right hand circle to land. This time I checked the plate when asked for the minimum circling height, so answered with the correct 410 feet. Slowed down and put in 2 stages of flaps. We had to extend our downwind leg due to other traffic landing. By the time I turned base I was back up to about 1000 feet, which wouldn’t be right for a low level circuit, and had to descend more steeply for a landing.


So where are we now. Having completed around 18 hours of IMC training, Roger thought that I would still need another hour or two before resitting the test. While my basic IMC flying on instruments is adequate – I can do straight and level, climbing/descending, turns, recoveries, partial panel etc OK – I need further practice to reach the standard required for ADF tracking and ILS approaches. He recommended a minimum of 1 hour, perhaps more.

My last flight at Lyneham

With the future of the club still very much in flux and flying at Lyneham now restricted to weekdays for the few weeks left there, it’s now very unlikely that I’ll fly again from the base. I’ve enjoyed having access to the tremendous facilities available there. The high quality of instruction, wide range of instrument approaches and discipline of using a full ATC has developed my flying skills considerably. To be able to do so alongside other club members and with some light supervision from instructors has made for a sensible next step after basic PPL training. The low club prices have also allowed me to enjoy many more hours than would be affordable at a regular flying school.

So what’s next for my IMC training?

With the continuing uncertainty over the club’s operations in the coming weeks as it moves to a new base, and having been unable to arrange IMC instruction at weekends, I think it’s most likely I’ll have to finish the course off at a commercial flying school. It would seem a waste to have got so far and not complete the rating. Trying to put in a full day’s work followed by an hour’s drive to the airfield and learning a complex new flying skill has been very demanding. Switching between three different instructors (all extremely good but with slightly different techniques) has also had an impact. For me it really would make more sense to do this at weekends.

This will mean finding and getting to know yet another instructor, learning the local approach procedures at another airfield and satisfying a different examiner that I’m up to scratch. In the long run, perhaps that might be a good thing – it will ensure I am at a higher standard before being let loose on an IMC conditions for real. Roger accepted that course of action and signed off the theory test which I’d passed in April on the application form. My logbook already has the course completion signed off by another instructor, so this should be acceptable at any other flying school. Roger also pointed out that my IMC training records would also be made available for use elsewhere.

So it was with a heavy heart that I left Lyneham for the last time. With so many having worked there for much longer than the 6 months I’ve been using it, I am certainly not the only one who will miss it.

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