Sunday 2 March 2014

Nudge nudge.

I think I’ve finally got the hand of instrument flying. Finally.

A little bit of background for the blissfully ignorant, as a bog standard PPL wannabe, I am learning to fly VFR. That’s Visual Flight Rules. Basically I have to remain clear of cloud and maintain visual reference to the ground at all times*. I’m not allowed to fly through cloud for example. Obviously this only works when the weather (especially the cloud base) cooperates, we call these VMC or VFR Meteorological Conditions**. People who do this kind of stuff for a living and need to fly when it is a little cruddier, in IMC (Instrument Meteorological Conditions) learn a whole other set of skills. 
Basically how to fly when you can’t see out of the window. Flying under Instrument Flight Rules (IFR)

As a PPL I’m not expect to master the exotic art of IFR hold and intercepts and other scary stuff (thank god!) but I am expected to master a certain amount of instrument flying. I need to acquire 5 hours in total during my training and during my flight test I’ll be expected to carry out certain manoeuvres under instrument conditions.

In order to stop a trainee pilot peeking out the window, you don a stupid device which I like to call the “Cone of Stupidity”. It makes you look like a demented budgie and you start to act like one as well.  Here’s what a pilot looks like wearing one***
 
pilot wearing a hood, I have to resist the urge to peck people whilst wearing one.

As RTH has mentioned previously as well as blocking your view of outside, the device renders you instantly mute and incapable of speaking, just like a budgie with a blanket over the top of the cage. I reckon Bob puts me under the hood to stop me swearing!

The fundamental principle of instrument flying is very simple. Your instructor assigns you a heading and an altitude and you do your very best not to deviate from them. In order to stop it getting away from you, you employ a “selective scan” technique. The primary focus of your scan is the Attitude indicator,as below
 
Attitude Indicator, mine normally reads "stroppy"
This acts like an artificial horizon, ground is brown, sky is blue. It tells you if your wings are level, if your nose is pointing towards the ground (descending) or towards the sky (climbing). To cross check your heading and altitude you use different instruments in your standard six pack , depending on what you are trying to achieve, but your main ones are the heading indicator ( which way you are pointing) and the VSI (how fast you are going up or down).
All pilots have a six pack, even me!
The trick is to flick your eyes between these instruments to get a good handle on what the plane is doing and match that to what you want it to be doing. If you are at 1800 feet and you need to be at 2000. Then you check the AI shows you in a climb and that the VSI is showing you ascending as well. At the same time you need to cross check your heading indicator to make sure you are still on course.

Every rookie pilot makes the same two classic mistakes. Fixating on one instrument and/or overcorrecting. I’d managed to get a handle on the first quickly enough by providing a running commentary on my flying. The latter though was a challenge.

My natural impatience means that I have a tendency to wrench the plane from place to place. What happens is that you yank the plane around, overshoot your heading/altitude and so need to compensate back the other way. You do this too quickly and end up having overshot the other way. And so the vicious cycle goes on and on until you either give up or your instructor takes pity on you.

Finally though, I’ve got it. You don’t fly the plane under the hood, you nudge it. Once I’d figured this out I finally managed to fingertip fly the plane under instruments for a good 0.3 of an hour, barely breaking a sweat.

Nudge it don’t yank it.


*If you watch my video “unexpected cloud”, you can hear the controller helpfully reminding me to remain VFR

** Gotta love that acronym within an acronym

*** I stole this picture from the interweb-if it’s you drop me a line and I’ll credit you. You look much better than me wearing one!


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