Unfortunately the cloud base was around 1700ft today and the safety altitude was 1900ft along my route from J28 to Hartley so we decided to change it up a bit and do something new – Simulated Instrument Flight (Exercise 19). To be honest I didn’t know this was a thing, but it was surprisingly fun and I had quite a few take aways.
In the skills test, there will be a simulated test of instrument only flight for the scenario where you may inadvertently enter cloud which I would not be rated for. The task will be to reverse 180 degrees, and would not be done in cloud only simulated. We also covered climbing and diving simulated instrument flying, this would not be covered in the skills test but helps to gain an understanding.
It’s simulated as it is not done in cloud, but a hood is worn in order to mask the view outside while still being able to view the instruments. A little tricky to put on!
Airspeed Indicator, Attitude Indicator, Altitude Indicator
Turn Coordinator, Direction Indicator, and Vertical Speed Indicator
During straight and level flight, it’s a T motion to look at the 4 main instruments, always checking back in on the Attitude Indicator (AI) while changing, I should be looking at it every few seconds – I don’t think the order matters:
1. Attitude Indicator
2. Airspeed Indicator
3. Attitude Indicator
4. Direction Indicator
5. Attitude Indicator
6. Altitude Indicator
I also said this outloud to try to get it fixed into my mind as I was going:
- Attitude is correct, wings level and dot is on the horizon
- Airspeed is good, as expected 90 knots (trying to observe if too fast or too slow)
- Attitude is correct, wings level and dot is on the horizon
- Direction (e.g. 230 degrees) on correct / slight correction required (and then make the change)
- Attitude is correct, wings level and dot is on the horizon
- Altitude is correct, holding steady at 1400 feet for example
- Repeat
It’s important not to get stuck on one instrument, and to continue to scan back to the AI between checking the other instruments.
The normal rate of instrument flying is called rate 1 (or standard rate) and is marked on the turn coordinator (TC) with a bold mark. When doing the turn, the wings of the plane within the TC will turn to this bold marker which should be held in place to maintain the bank. Following this rate, it would be 3deg per second (45deg/15 seconds, 90deg/30 seconds, 180deg/1 minute, 360deg/2 minutes) – hence the time (2 minutes) written below the turn coordinator.
The required bank angle for a rate 1 turn is 10% of the airspeed (90kt in my C152) plus 7. So at 90kts, 10% is 9kt plus 7 = 16 degrees.
Now to begin the turn, the instructor may specify the direction to turn and the heading to turn to, or leave it up to me to work out either of them, e.g. to turn right from 0 degrees north to 180 degrees south.
- Begin by asking if it is safe to turn in the direction that you want to go
- Begin the turn, holding that 15/16deg (better to be under slightly)
The ‘T’ motion is then adapted to primarily between the AI and the TC to ensure the turn is happening, but still checking the others to know when turn out.
Turn out around 5 degrees before the target direction, and it needs to be a confident/directed level out.
Also a good reminder of APT and PAT – when coming out of a climb hold that attitude, reduce the power, wait a bit then trim. Timing that descent, carb heat on 100ft earlier and introduce power 50 feet from target to stop sinking below
To climb, hold the spot towards the 1 mark on the Attitude Indicator (a little way from the horizon line). Small amount of right rudder required. Trim when happy to maintain that climb.
To descend, hold the spot just below the horizon line – nowhere near as much as climb, basically the top of the spot should be touching/grazing the horizon line. Small amount of left rudder required.
I don’t know why but I really enjoyed it! I had a smile of my face. I think it’s really helped me appreciate the instruments, some of which I had not really used to such degree before and also the precision of actions. Logged 40 minutes in my look book under simulated instrument flying – 20 more minutes to do at some point as apparently good to have an hour.
Some things to think about for next time:
- Listen more to the sound of the engine, on a few occaisions it would have avoided more changes and to know I was too high or too low and therefore altitude up and down
- Hold that landing off for a few more seconds just to lose some speed
- APT/PAT reminder
- Hold that attitude for what you think the climb should be
- On take off, get stablised and think about drift and direction
- Revise FELT checks