Night Flight 11th October 2019
This was a typical first night training
flight conducted in Piper Tomahawk C GDDG from Boundary Bay
Engine start: 19:07, Takeoff 19:27, Final Landing: 20:57, Engine stop: 21:00.
Initial discussion on the ground included a
description of the Somatogravic Illusion in which a pilot
faced with nothing to see ahead senses incorrectly that the
aeroplane is pitching up as it accelerates in the climb shortly
I had a real experience of this at Sechelt one night when the student pitched the nose down in the Cessna 152 we were flying. I was delighted, I have control as I quickly raised the nose again. The student was shocked, and the learning factor Intensity was satisfied.
The somatogravic illusion can be experienced taking off into the blackness, and into low cloud/fog in the day time. Any time there is nothing to visually reference after takeoff.
Ensure the instruments display a positive angle, and a positive climb after takeoff; trim, and relax.
There is also the Black Hole Illusion where on final approach the lack of visual clues between the runway and the pilot can cause that pilot to fly a low shallow approach with the danger of a CFIT: Controlled Flight Into Terrain.
The Tomahawk was fueled and a flight plan was filed with Kamloops Flight Information Centre.
Inspection using a torch/flashlight is very effective as you focus on each item with no distraction.
The navigation lights are turned on before the engine is started.
If a beacon is fitted then this is also turned on. Consideration should be made if very bright strobe lights are to be used.
There is ramp and taxiway etiquette to be
We must not blind people on a dark night, never shine a landing light into the cockpit of another aeroplane, and avoid close encounters with bright strobes.
A strobe light on the top of the fin is best, wingtip strobes however must be considered for their distracting effects.
There is good reason for turning strobe light off when flying in darkened clouds, these have a disorientating effect. On the ground they affect the visual acuity of personnel in the vicinity.
Personally, in most light aircraft I prefer to turn wing tip strobes off on short final to avoid their distracting effects when one must concentrate on the landing. This is especially important if landing in the rain or drizzle.
The first night flight is an experience
flight. An introduction to the sensations and beauty; flying in
We taxied to Echo for the runup and pre-takeoff checks.
There was a Cessna already there and so as we approached the landing/taxy light was turned off so as to not shine it into the other aeroplanes cockpit. We turned and switched the light on again as now it would not be a concern to the Cessnas crew.
Takeoff was at 19:27 local time with the
nose raised a little until the nosewheel was clear, the aeroplane
allowed to lift off gently, and then trimmed as necessary for a
hands off climb.
It is very important that flight where the instruments might be desired, such as soon after liftoff in the dark, that abrupt and sudden movements be avoided.
Instrument flying requires smooth hands.
Haze was noted around the landing light beam
as we climbed out, and then the light was turned off for a better
The light beam is a good indicator of moisture content in the air, as is the airport beacon, and any light on the ground.
Such indications are important for considering the prevalence of carburettor icing, as well as the chance of fog.
As an aside, in Canada the ground electrical
system is at 60Hz, and this can be used with white lights on the
ground to evaluate the accuracy of the tachometer through its
strobing effect with the propeller. In the UK it is 50Hz, and
likewise the strobe effect on a propeller can be observed.
Change the RPM until the propeller appears stationary and the tachometer should read a multiple of the frequency of the electric lights, 50 or 60 Hertz, i.e. it should appear stationary at 1,000 or 1,200 RPM.
(2,000 or 1,800 RPM on the runup).
The route took us along the Fraser River
below the 1,200 foot base of the control zone. Even so, I dialed
up Vancouver Tower on 125.65 and told the controller we would be
routing below their airspace.
Shortly after the Pattullo Bridge,Vancouver Tower cleared us to climb to 1,500 feet with a west turn towards Vancouver Harbour.
We must be careful with the clearances we accept as the law requires us to be at least 1,000 above the highest obstacle within 2,000 feet of the aircraft. Since we were now clear of CYVRs approach/departure paths I requested 2,000 feet and was cleared to this altitude.
At this time of night Vancouvers
Harbour Tower is closed. This means making blind position reports
At night it is much easier to spot other traffic in the air. There was no other traffic in our vicinity, but still we reported about to enter the airspace, over the Second Narrows and the Lions Gate Bridges, routing up False creek, then departing eastwards, and leaving the zone.
The effect of autokinesis where a spot of light on the dark background can appear to move is something to discuss.
While on the leg between Patullo and Second Narrows the lights of Grouse and Cyprus mountains were used to discuss the false horizon illusions at night.
At night Vancouver is a bright shining
jewelery box with brilliant coloured lights, its a sight to
Consideration is now as to where one might go if the engine failed?
Here its not too bad as there are docks with open areas of asphalt and concrete, and anywhere you can transport a sixty foot container sideways is a potential runway.
At night the availability of forced landing places is usually hidden in the blackness. It is often easier to find somewhere to go when over a brightly lit industrial area.
Of course theres the old adage, aim for the darkest piece of ground, turn on the landing light at 200 feet, and if you dont like what you see, turn it off; applies if the engine goes quiet on a dark night.
While circling over Vancouver I selected
Vancouver Airports ATIS (124.6) on the right side of the radio
and pressed the Monitor button. I was interested in the
temperature-dew point spread, and it was +6ºC/+4ºC.
This was only two degrees, and such a temperature can drop easily to the dew point on a clear night close to the ground due to radiation. The ground radiates its heat into the clear sky and both Advection and Radiation Fog may form.
We did a turn over Vancouver and then routed
eastwards to SFU, and then descended to the Port Mann Bridge to
join the downwind for a touch and go at Pitt Meadows Airport.
If you are uncertain of your height, use the soft field glassy water technique to let the aeroplane down with a little bit of power.
In the Tiger Moth at Redhill this worked superbly with the notorious Tiger Moth settling on the mainwheels without any bounce; delightfully easy. Yes, Ive flown a Tiger Moth in the dark.
In the Tomahawk this method resulted in a very gentle touchdown.
Next place was Abbotsford, and so we left
off the downwind to follow Highway 1.
Up here at 2,000 feet we looked around the Lower Mainland to pick out the flashing airport beacons amongst the myriad lights strewn across the landscape.
Abbotsford ATIS stated the temperature as
being 8ºC and the dew point 4ºC; a comfortable four degree
The runway in use was 01, but since the wind was light and variable Tower cleared us to right base for 19.
This was convenient as here I requested Abbotsford Tower to demonstrate the variable intensity lighting. In very poor visibility Abbotsford is able to brighten the lights to brilliant effect.
We touched down on the well lit and very
wide 19, and then took off again with a right turnout to Langley.
The flare height illusions, between narrow and wide runways, needs to be discussed.
Langleys 2,100 foot long runway 01 was
in use. It is equipped with PAPIs to guide you to the runway, and
this requires precise control of speed and approach angle to be
able to do a touch and go on this runway. We did an approach with
the full knowledge we may have to go around, which is what we
The objective on this flight was more about experience than proficiency.
Left turn and head back to Boundary Bay
where runway 25 was still in use.
Unlike the other runways this evening 25 does not have VASI (Visual Approach Slope Indicator) or PAPI (Precision Approach Path Indicator) and so the aiming point I like to use is three white runway lights into the runway, between these is the point of zero movement or aiming point on the runway.
Since our circuits would put us beyond our flight plan time I asked the Tower to close our flight plan as we approached the runway. There would be no need for a flight plan now as we would be talking to ATC throughout.
We did a further six landings including two
with the landing light turned off.
One time the landing light was forgotten until short final and the approach was destabilised when Rory looked down to find the switch!
Having a stable final approach is important; if it is not to your liking go around. I took control and fixed it, and another lesson was learned.
Enough for tonight, the next circuit was our final one, and it was time to go for a beer, and to debrief.
12th October Flight
Instrument proficiency is important when
flying at night.
Theres a reliance on it when taking off from a lit runway into darkness ahead with the risk of the somatogravic illusion spoiling your evening. This means ensuring you have positive indications of climb, positive rate, positive climb, and airspeed after you depart.
For many pilots the five hours instrument
flying required for the Canadian PPL is in the largely forgotten
So we reviewed the instrument panel. The Attitude Indicator (AI)(Artificial Horizon) and the Tachometer are Attitude + Power, and the remaining instruments are the Performance Instruments.
Attitude + Power = Performance
The scan of the instrument panel is
briefed. How the scan centres on the AI and goes to the various
performance instruments as well as occasionally the tachometer
(power, Manifold Pressure if fitted).
In VFR we reference the horizon, and then maneouvre the aeroplane to achieve a change, referring to the instruments after we have done this. We should never look at the instrument that shows the change we actually want, until the aeroplane is established and trimmed for the attitude change.
So if we want to increase the airspeed
we add power, lower the nose, and trim
We do not look at
the Airspeed Indicator as this diverts us from flying the
So like during day VFR on instruments we add power while we refer to the Attitude, scan the ball, and scan the altimeter. Back and forth, once in a moment check the heading, and trim the aeroplane. All is well? Check the airspeed, is it what you want? Adjust as necessary.
Turning: We scan from the Horizon to
the Heading Indicator (Directional Gyro), note the heading and
then back to the horizon. How much change of heading do we need?
If its only a small change then consider less than a Rate One turn, or even simply applying a little rudder if less than 5 or 10 degrees.
If its thirty degrees or more then a Rate One turn is preferred.
Rate One is achieved at near enough a bank angle equal to 10% of your airspeed plus 5 mph, or 7 knots, and so if you are flying at 80 KIAS this would be 8 + 7 = 15 degrees.
Roll the aeroplane to the required bank angle using the Attitude Indicator, hold this bank, scan the turn and slip or turn coordinator (T&S) to confirm rate one, ball in the middle, back to the AI, then to the Altimeter, and back again. Repeat until you are comfortable, and then scan the Heading Indicator occasionally. Roll out half the bank angle before reaching your heading This means 15º bank ÷ 2 = 8º before the heading is reached.
A Rate One turn is equal to 3º per second, and so if you divide the change of direction by 3, you will know how long the turn should take.
Rate On turns to the left are more stable in aeroplanes with right turning propellers such as Cessna 152s as the gyroscopic effect of the propeller is to apply a nose up pitch due to the precession effect of left yaw. Cessna POHs specify left Rate One turns in the Amplified Emergency Procedures for good reason.
Note that the Turn Coordinator works mostly through Yaw, and so it will indicate roll even with the wings level if the aeroplane is flying cross controlled.
Changing altitude; glance at the
altimeter and how much altitude do we need to gain or lose?
Small changes require little effort other than changing the pressure on yoke or stick.
Bigger changes require, Power, Attitude, and Trim, where the power is increased or decreased, the nose raised or lowered with reference to the AI, and these changes require scans of the Turn Coordinator (T&S), the Heading Indicator, with occasional glances at the Airspeed (trimmed?).
We are limited in the amount of climb performance, but not so much in our descent performance.
But all changes should be smooth and gentle; a pilot needs to be relaxed when flying instruments, no dramatic changes, and always in trim.
Another rule of thumb is to recover to level flight at 10% of the Rate Of Climb or Descent. i.e. 500 feet per minute?, apply elevator to return to level flight 50 feet before reaching the desired altitude. Level off smoothly, Attitude, Power, Trim.
Much of instrument flying can be done using
the rudder only. Indeed the Emergency Descent Through Clouds in
the Cessna POH requires this.
Be aware of the asymmetric effect of a yoke as fitted to a Cessna. The relaxed left hand and arm resting on the left side of the yoke will tend to cause the aeroplane to roll.
Ensure the aeroplane is trimmed, and then take your hands off the control wheel when you need to do something else like look at a map, tune a radio, set a heading bug etc.
Trends are an important
part of instrument flying.
Are we high, are we low?
To correct a small altitude error within 200 feet simply apply enough force to obtain a 100 to 200 rate of change, to Trend the altitude back to where you want it to be.
Trends make corrections smooth, without big changes, allowing easy control of the aeroplane.
We departed Boundary Bay at 19:10 local time
to go out over the water just south of Point Roberts.
For me this is fine as I can see lights all around the horizon, except to the south There was no visual indication here, and so even I would need to reference the instruments when turning through this direction.
This the first lesson was to concentrate on
straight and level flight, some speed changes, and rate one turns
to reciprocal headings as we paced to and fro east and west.
Over the water there is no cheating under the hood, you are flying in a void, and soon enough the leans were experienced Trust your instruments.
Leans are the body being confused. When the
aeroplane is flying level you are certain its in a bank
Do a steady coordinated turn and the body realigns itself with
the ball, thinks it is level, but you are turning. Roll level and
you are certain you are turning! Check your instruments.
It takes time for a scan to develop, for a person to relax, and settle with an in trim aeroplane making small movements, small corrections for accurate straight and level flight, and accurate turns. But this was achieved well enough to be able to return to the airfield under the hood with guidance from me.
Established on final I took control, and Rory removed his hood. He had spent forty five minutes under there, more than enough to cause him fatigue.
I will take a student to the point where learning has peaked, and before fatigue takes over we conclude the lesson.
I did the landing at 20:12.