CPL day 14 - more instrument flying

Yet again, what looked like a good day for flying on paper turned out to be kyboshed by low cloudbase. Still, above the lowest cloud was about 2-3000 feet gap before the next layer, so it meant I could do some more instrument flying. Because Dick was on holiday, this was my first trip with Brian, an instructor I've never flown with before.

The aim was to do at least doing unusual positions work. This is where the instructor makes the plane go a bit like a roller coaster and leaves it in an "unusual position" for you to recover from as if you had somehow got yourself into it. The technique is first to check your airspeed:

• If it's decreasing then you are nose high so you put on full power.
• If it's increasing then you're nose down so you pull the power back to idle.

Then you roll the wings level before leveling off. If you have a full panel you would use the AI to roll level, but if (as in this case) you have limited panel with a gyro failure and therefore no AI or DI, you have to do it differently. You roll the wings towards level using the turn coordinator as a guide, but go past level to a rate1 turn the other way before rolling level. This is (I believe) because the TC can have a delayed response with high angles of bank so if you only roll level on first reaching, you may not in fact be level. Once you are wings level you level out in pitch and let the airspeed bleed off/build back up before adjusting the power back to a cruise setting.

When we set off Brian said that he was going to go through all the basic instruments work in addition to unusual positions to see where I was at against the required standard. So we did a bit of basic climbing, descending & turning before having a simulated gyro failure and doing most of the rest of the trip on a limited panel. We did timed turns which worked out generally better than my earlier trip, though it's always difficult to get an exact rate 1 position on the TC and maintain it to correctly roll out onto your desired heading. But on the second attempt we got to within about 10 degrees which was not to bad. We then did unusual positions which went well enough once I was reminded of the limited panel technique I described above.

We also did intercepting of radials from a "pseudo" NDB of Minster Radio on 666KHz which is located in the centre of York. This was a bit more challenging than just tracking inbound/outbound and involved calculating the best intercept angle to pull/push the needle round onto the required radial, but reducing the intercept angle as the needle approached the desired radial so as not to overshoot. When trasking outbound from the beacon, you have to be on the ball and turn immediately the needle stabilises onto your outbound radial or you very quickly overshoot and have to go through the palava of intercepting it again.

It's relatively easy when tracking inbound using the "push the head" technique. This is where you adopt a heading greater than (eg. 090) the heading the needle points to (eg. 060) which will cause your relative heading to decrease, hence pushing the needle towards your desired radial (eg.030). But when you're intercepting outbound you have to use the "pull the tail" technique. This means that if you to intercept 030 outbound, you want the tail of the needle to be on say 030. If you're currently on 060 outbound you need to adopt a heading of say 000 which is less than your desired heading which will pull the tail of the needle towards your desired 030. Hope this makes sense to everyone - it's hard enough visualising it as a pilot when you're not flying! If not, don't worry - I think you can probably live a happy an fulfilled life without this :-)

Everything went pretty well, and then back on a full panel I flew headings as passed to be by the instructor to route me onto final before landing which went very nicely. In the debrief Brian was happy with all my instrument flying and said he didn't think there was any need to do any more until later on, perhaps when they put the screens up on a diversion leg. So that's good news as it means I'm well on track for the twin once the nav is up to scratch.