Level Flight And Turns
Harder Than It Looks
Sunday, September 03, 2006
Flying Hours Today 1:10, Total 4:10
Ex 6 Level Flights Turns. Lot of wind – 35kts @ 1500ft, 250/20 EGSY on approach
All three controls together. Doing it formally as we had already had some practice in the previous lesson.. Level flights and turns, climb and descending turns will be done later.
Part 1, straight and level.
Cyclic for attitude and therefore leading to airspeed
Collective for Height, and therefore power
Pedals to control yaw and therefore balance.
So, Attitude and power = performance, just like in the world of fixed wing. In this case the settings are for straight and level get the correct setting at 70kts with 20” of manifold pressure. Question – what is 20” of manifold pressure? Is it a direct correlation to the amount of power? Why not just use engine RPM as in the case of my PA28? Ah! But we have variable pitch blades and so power is used – I need to think about this and read up on constant speed propellers again and to consider why the Diamond Star has a power setting and a constant speed propeller.
We also looked at the power curve for a helicopter. Similar at first glance to that for a fixed wing aircraft. Only in this case it is OK to look at the back of the ‘drag curve’ as that is used for slow speed and approaching the hover.
More power at lower speed, but remember in the R22 this is all done automatically. With the governor taking care of the collective and throttle. So we need to look for 70kts at 20” MAP. And if we want to climb or descend we adjust our attitude and power, but how does this compare to fixed wing for climb / descent (c.f. attitude)
Once we have the standard 70 @ 20 we can begin to adjust our speed:
Increase Speed Decrease Speed
Accelrative Attitude Decelarative Attitude
Flapback will occur Flapforward may occur
Raise the collective (to 80kts use 22” MAP) Lower collective (60kts @ 18”) – use the power curve
Balance – left pedal Balance – right pedal
Monitor ASI/VSI but don’t chase
Select attitude
Adjust power
Balance
Intro to the safety zones for take off and cruising. I’d asked about doing hovers somewhat higher off the ground, but this isn’t the case due to potential of crashing violently so we have to do them low down. I wanted to hover at height, but was made aware of vortex ring, today might be possible as it was so windy that even though we would be stationary over the ground at some height, we would have a decent airspeed.
Part 2 of the lesson – turning
I’d struggled with turning so far, even though we hadn’t done this formally I was having an issue with getting a ‘feel’ for the turn. It seemed weak compared to fixed wing. I found out why. In the previous lesson I was asked to fly us to a land feature at, say, 10 o’clock. Through years of computer gaming I simply pushed the cyclic to 10 o’clock. Thinking about this I was turning us slowly left and developing a nose down attitude. What is needed for a turn left or right is to move the cyclic directly left or right. Not forwards, not backwards.
We covered airmanship, as always during ground school. And I learned something here, when turning left, look right first of all to make sure nothing is heading towards me, as when I’ve turned I will lose visibility of what is to the right and behind me. It is always interesting to get a different instructors take on things and this is a great little thing to consider.
Turn with 15 to 20 degrees angle of bank. I hadn’t noticed, but there was no AI (or DI for that matter) in our R22 – indeed there are no gyroscopic instruments on board. So we have to be visual and make a mental view of the angle of bank. 15 to 20 degrees is about 3/4th of a half of a half of a quadrant (i.e. 90 to 45 to 22.5 degrees and then 3/4th of that). And during the turn fix my view through a convenient point on the windscreen (a dead fly will do) so that I have a feel for the rate of turn and know when my target heading is in view. Use the pedals to keep me in balance.
And so out for the lesson. The A-Check and pre-flight had already been done so we were straight in and ready to go. It was blustery with 15kts gusting to 25kts, but in helicopters this isn’t such an issue as they can simply fly into wind, or so it would seem. A new start up check list was produced, slightly different to what I’d been using before. It still feels complicated and is by no means commited to memory. Having to hold the controls with the checklist loose on my knee is interesting. The instructor is still doing the radio calls.
Great take off and soon into the air. ATC asked for cloudbase and wind check. Cloudbase we reckoned to be about 1800ft from our 1500ft AMSL height. We couldn’t do the wind as yet.
I was soon in control as we flew south on the west of the M1, balanced in a nice configuration at 70 / 20 and being buffeted by the strong westerly. I slowed down and speeded up, slowed again to around 40kts to overcome my fear of stalling as a fixed wing pilot does! All the time maintaining altitude, give or take a 100 or so feet which wasn’t bad on such a blustery day.
We turned into wind and the instructor brought us to a hover at about 1500ft. The ASI indicated 35kts so we called back to Sheffield to pass the report of a 35kt westerly at 1500ft. I wonder if any brave fixed wing pilots would be going up today before the wind grew even stronger. Strangely in the R22 it is quite peaceful and calm, you wouldn’t believe you were in such a strong wind.
We turned and headed north and east again, speeding up and slowing down. Using all three controls and keeping level. At times we had the wind behind us and we were shooting across the ground, probably at a 100kts in some cases.
It was time to learn to turn, but to use the cyclic properly. I soon mastered left and right turns and before I knew it I was following the A57 on the east of the M1 and along the streets of Todwick. Great fun.
All too soon it was time to return to the airfield. I made the inbound call from the Rother Valley – I’m so glad that I have Radio Telephony experience, it would be so much harder to have that as additional workload on top of learning to fly a helicopter. We hadn’t heard any traffic at all so made a straight in approach for the southern apron along the R28 extended runway (?). It was getting gusty at the lower levels so the instructor took over. Much to think about and do as we got lower and lower, but generally a constant forwards movement at, perhaps 60kts and then only when close to ground do we look to stop and hover then touch down. I could now see that two Cessnas were powering up and ready to go flying – they would have a nice trip with almost vertical climb out and then a 35kt wind blowing them eastwards.
It was quite choppy but I elected to go for some hover practice. Starting in to wind first and keeping sure I didn’t get weather cocked, but it happened too often and I couldn’t catch the turn in time and there were many calls of ‘You have control’ back to the instructor. At one point I did get the hang of things and hovered for quite some time, but alas my efforts would unravel by the actions of a freak gust. This was a great improvement though, I felt I was doing much better, and to be learning in 20kt gusting winds was a great challenge.
To give the engine a rest we did a short stop, at 50kts or so and quite low then flare and stop. I’ll look forwards to these soon. Then back for a few more minutes of hover, watching the first Cessna depart then crossing R28 to the apron while the other completed their power checks. A nice touchdown then time to complete the shutdown checks. As with the start up checks we do things with the checklist but have to commit a few actions to memory as they have to be done quickly, and at all times having a firm hold of the throttle just in case.
We left the R22 and returned to the office, the next student was already in but the rest of the days activity had been cancelled due to the worsening weather. My next lesson is in a few weeks – I can’t wait!