Sunday 7 November 2004

Trust Your Instruments


Flying Hours Today 1:00, Total 10:15

The weather forecast over the weekend did not look good for flying lessons, but it was expected that the overcast cloud would clear early on Sunday morning. My instructor called me just after 0700hrs and suggested I make it to the flight school by 0900hrs and we would review the weather at that time.

This wasn't such a bad plan as I was intending on sitting my meteorology exam and so would need to be at the flight school today anyway.

On arrival I could just make out small patches of blue sky through the thick stratus. The cloud cover was still really 8 oktas, it couldn't be classed as broken, but things looked up.

As we were going to fly to Full Sutton (EGNU) again, where the cloud cover further east was forecast to break up, we decided to take to the skies for another flying lesson.

Today's lesson was to be all about approaches, and getting the appropriate visualisation of the runway confirmed. A short briefing on this, the PAPI lights - not for our use - and the importance of an accurate and fixed glide slope. You don't want to be approaching the runway at different angles time and again, learn the approach well and then the landing will be a piece of cake. Remember: it is power to control altitude and attitude to control air speed.

We booked out for a Special VFR departure from Leeds where the instructor would be doing most of the flying, then moved out to the apron to refuel G-BODD. All the usual checks completed, and instructions to taxi to runway 32 given.

A different route this time, keeping us from the usual Foxtrot taxiway we were instructed to take Golf then Lima at Leeds Bradford (EGNM). It is striking how easy it becomes to get set in a pattern, I'd always left the Multiflight apron via Foxtrot and duly headed that way, with a plan to then turn onto Golf and Lima, but was quickly prompted to make a sharp right turn to the correct entry on to Golf.

We had to wait at the Lima holding point for a Gulfstream - N16NK - to taxy by. By the sound of the pilot's voice and the time of day I assumed this had just flown in from the USA - but I could not be sure.

I completed the power checks then moved out to R32, initially heading 14M to backtrack at Delta then the usual take off. Slight wind from the left so to factor this in.

Instrument Flying

"The three fundamental skills in instrument flying are: instrument cross-check (also known as scanning the instruments); instrument interpretation (understanding their message); and aeroplane control (directing the aeroplane along the desired flightpath at the desired airspeed using attitude flying)."

From Trevor Thom's The Air Pilot's Manual 1
Very soon we were flying in cloud. The instructor took the opportunity to get me some instrument flying practice. Flying completely by the attitude indicate with no visual reference outside. We turned to the east, saw a break in the clouds over Harewood House and then we were back in the clouds. As we headed to Full Sutton it was becoming clear that the cloud was not improving and so we maintained radio contact with Leeds and requested a Radar Information Service. At very short notice the lesson changed to one of instrument training.

Instrument flying was not quite as challenging as I had expected - although I was only doing the extremely basic work of turns and maintaining altitude.

Although the attitude indicator is the main instrument to monitor during instrument flying, it has to be remembered that the instrument could still fail. Therefore it is imperative that we scan the other instruments to back up what the attitude indicator is telling us.

If flying with our wings level then our heading will not change as we are not banking.

Iif our attitude is correct we will not climb or descent - if expecting to be in straight and level flight.

So remember to scan the instruments : dot for altitude i.e. if the dot in the centre of the attitude indicator is aligned with the attitude dot - dot on dot - then altitude will remain constant, and wings for direction.

Every few seconds scan right to the altimeter and then down to the direction indicator. We practiced a few turns left and right, using rate one turns in IMC conditions. Get the rate one bank then hold that for the turn, level out with about 10 degrees remaining on the DI. Climb and descend as in VFR conditions. I managed to maintain 3000ft incredibly well, it almost seemed easier than in VFR conditions.

The instructor had also been navigating using radio nav aids. We flew over Drax Power Station, about 30 miles to the east of Leeds and felt the turbulence caused by the cooling towers, this made the instrument flying more challenging as I had to handle the turbulent motion and maintain heading and level.

As is always the case it was soon time to return to Leeds. The instructor made the calls to receive the vectors and we headed on 280 back to the airfield.

It was interesting to hear the radar service gave us indications of other aircraft in our vicinity. Quite unnerving to know that others are flying near by with no visual contact - the traffic controllers certainly do an excellent job and in one case we took their advice to change heading to maintain distance with another, unseen, aircraft.

Now the lesson got really interesting as the localiser was brought into play, along with the glide slope indicators. The instructor was making some rapid calculations on heading, direction, height, cloud base etc. etc. as I just flew the aeroplane.

Shortly we were flying over Leeds as I could see Kirkstall Abbey through a break in the cloud. We were making an instrument approach on R32 as is done by the big jets, this is the first time I had made this approach as a pilot, having lived it maybe a hundred times as a passenger.

We broke clear of the cloud at about 600ft aal. The runway was lit up in all its glory. The approach training was back on as I targeted us for a point just to the right of the PAPI lights. Closer and closer, dropping the power as we neared the ground, back pressure, then allow the aircraft to fall gently onto the concrete. The instructor was in control for the landing, but it was the closest I had yet come to making a landing.

The instructor made an excellent point about landings - you are not trying to fly the aircraft onto the ground, i.e. making a precision approach where you intercept the ground at almost zero vertical speed, instead you aim to fly level with the ground, then use attitude to lower airspeed and, consequently, lift and then the aircraft will slowly fall onto the runway and you have landed.

Taxy back to Multiflight West then back to the flying school.

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