G-UFCB : Cessna 172SP
Another early morning flight and as is becoming tradition now, I was met by yet another instructor I’ve never flown with before (6 down, 2 to go).
Briefing
We’d be looking back at ‘Best Rate of Climb’, ‘Best Angle of Climb’ and doing some work with full (30 degrees) flaps.
In the past my brain has had a tendency to blank at key moments of briefing quiz questions – today it was on better form and I got my Best Rate of Climb Speed = Vy and conversely that Best Angle of Climb Speed = Vx spot on. You read it, you think it’s sunk in, 2 weeks later someone asks you and it’s 50/50 whether it leaps to the top of your mind.
Another set of numbers to remember:
Vy = 74 Knots
Vx = 65 Knots
For convenience though most climbs/descents are flown at 80 Knots, you only really need to worry about using Best Angle of Climb if you’re doing a short field / obstacles at the end of the runway take off (e.g. Need to get maximum altitude the shortest distance).
We’d be looking at full flaps and how poorly the Cessna 172SP climbs if it has full flaps lowered.
Finally we’d be looking at getting into final approach configuration of full flaps and 65 knots indicated airspeed.
The weather was looking good for at least the next hour, no royal flights would be anywhere near and my instructor would be handling the paperwork of the flight……. In the mean time, I’d check the plane (G-UFCB).
Plane Check-Out
The lesson would be going no further if there was anything ‘exciting’ to report, so thankfully this was an uneventful checkout.
I keep getting lumped with Charlie Bravo……today I’m informed there’s absolutely no hope of being trusted with a go at landing it because it’s nose wheel is in poor shape and the instructors are trying to keep as much weight off it as they can, for as long as they can during landings (Just what you want to hear before taking off in a plane!)
It’s got a touch over 10 gallons of fuel in each tank and other than the issue with the nose wheel, it looks as good as I’ve ever seen Charlie Bravo.
It won’t start….
Well this was a first, aux. fuel pump was used to get some fuel into it the oil temp was outside of the green (being the first flight of the day, that’s not exactly surprising). All going well, until I set the throttle and turned the key with my other hand on the mixture….splutter, splutter, nothing.
My instructor said “that doesn’t sound good.” – meanwhile I was having flash backs to the Extra 200 that wouldn’t start – but he told me to try that again. I did and got nothing more then spluttering.
Third time lucky…….ahhh Charlie Bravo, why do you treat me so?
Taxi & Radio Ga Ga
It was bound to happen….all of my radio calls to date have been good. On this lesson my taxi clearance request was a near stumble through of a call. I made the mistake of not prepping in my mind, the sentence I was going to say and then when I went to just say it. It was rough – clear enough for ATC, but could have been so much smoother.
I blame it on having a new instructor.
We taxied out to the holding point nice enough – it’s the small details like half looking like you know what you’re doing on the taxi to the holding point that are the nicest of wins. Only a few months ago back in August the whole thing was massively daunting and my taxi was nothing like as nice as this.
Take Off
My instructor had been absolute right from the briefing that he’d be doing this take off due to the nose wheel. Other instructors talk through the take off, this one did the same but it was almost a well rehearsed script rather than talking through the actions.
However, what I did like was being talked through the altitudes with respect to what our failure options were. So for example, at 500ft there’s no hope of turning around, if the engine fails we must land somewhere ahead of ourselves (This is because in the turn we’d lose 500ft), at this altitude then our failure landing point was likely to be a nearby rugby field (and pray for not scoring a conversion I guess!). At 750ft, there are some school playing fields that we could probably reach and finally at a 1000ft we have plenty of options, including the preferable one of turning around and making a run for the airfield we’ve just taken off from.
My instructor does the climb to around 2,000ft. As we’ve never flown together before (and rather frustratingly because he didn’t do part 1 of this lesson with me), he quite rightly wants to see what my climbs are like.
Climbing to 3000ft.
“Ok, you have control…..Climb to 3,000ft for me.”
Full power goes on, I set up the attitude to give me 80knots indicated airspeed and we start soaring up at around 500ft/min.
Approaching 2,900ft I begin to level out of the climb, but I guess being the first touch of the controls I’d had all flight, I level out slowly I trim the plane up slowly and I do a fairly poor job of “holding” the plane level as we hit 3,000ft – by the time it’s all trimmed up and I look back at the altitude, I’ve overshot by 150ft (and just to add insult to injury I’m 20 degrees off my original heading). Damn it! These are the moments where you just get tired of the psychological effects of being with someone you’ve not flown with before. My instructor goes into a recital I’ve heard before about accuracy and that we’d try that again (in short that overshoot has just wasted 5 minutes of this lesson [2 minutes to get back down to 2000ft, 2 minutes to get back up and some lookouts and chat in between]).
The trick now, as with anything is to not spend the rest of the lesson beating myself up about the screw-ups to this point and to just crack on and fly the plane.
The descent back to 2,000ft is spot on – a few seconds to look around, set the heading bug and it’s back on full power and climbing up again to 3000ft.
This time everything is a bit faster, a bit more absolute in ensuring the plane stays level as I begin to level out of the climb. We’ve not drifted more than 1 degree off course and by the time it’s all trimmed up it’s 3000ft, +/-40ft. My instructor calls out “Now that’s much better.”
I got the impression that he was now happy I could climb/descend and that the first climb was just nerves…….On to why we were up here.
Best Rate of Climb
A climb at 80 knots feels like you’re climbing comfortably fast and getting to where you want to be, the nose is pointing up at about 10 degrees and it’s a fairly civilised angle.
For best rate of climb you want 74 knots, but you achieve this by changing the angle of the nose – power stays at full. As a result to get the speed down, the nose much go higher.
A climb at a Cessna 172SP’s best rate of climb feels like you’re aiming to get to the heavens. The nose is so high that you don’t have a hope of seeing over it.
Now compared to the climbs I’ve done in the Extra, this is all still very civilised……the Extra will go vertical quite happily for a long old time!
This is probably the first time you get a serious sense of speed in a Cessna – largely driven by the fact you don’t have a lot of time to be thinking about leveling out of the maneuver.
Descending with Full Flaps
By contrast when we descend with full flaps, it’s a descent at 65knots and you have the sensation of nothing but time……the reality is you’re descending quite steeply!
To do this maneuver, we bring the plane back into the white arc and under the VFE speed (Max. Flap Operation speed), lower the flaps to 20 degrees anticipating the nose lifting and then lowering the nose to maintain the airspeed – finally add on the remaining 10 degrees. One last hold of the attitude for 65 knots before trimming it up one last time.
We’re now descending at a leisurely 65knots – though the rate of descent is fairly vast at around 700-800fpm.
We spend some time looking at how different power settings affect the rate of descent:
– For every 100rpm reduction in power, the rate of descent is increased by 100ft/min
So if we want to descend slower, we can just add power……if we need to descend faster, we can reduce power. All while keeping the attitude the same.
This brings us on to a vital fact for the approach to landing:
– Attitude controls Airspeed
– Power controls Rate of Descent.
We did this a couple of times, the last of which was setting the plane up for the approach to land.
Landing
We were chased in by a something of 737 size so landing and getting off the runway was done at pace by my instructor.
Taxing back to parking there is a turn on to the main taxi straight which I now live for getting right……I overshoot the yellow line every time, the smallest of wins like this are actually the ones you remember most.
You don’t get to practice these little things as such, so you get one go per lesson and the moment you find you’re doing it repeatedly is the moment you can tick the box and feel like you’ve made a fluent step forward.