Dewpoint & Night VFR

[Colonel]

[quote]Why is the dewpoint spread important?[/quote]

It determines the cloud layer/ceiling, which
you probably want to stay under, VFR.


[quote]What causes the dewpoint spread to decrease?[/quote]

Temperature decrease (sun goes down) or
source of moisture can cause the dewpoint
to increase.


[quote]What's a visual telltale that you have dewpoint spread problems?[/quote]

One that scares the shit out of me, is moisture
falling (generally from an inversion) and I see a
scattered cloud layer developing below.  It can
easily become a solid layer.


[quote]What can happen when the dewpoint spread drops to zero?[/quote]

WOXOF.  But not necessarily.  Some mornings,
you will see the temp and dewpoint the same
(very common with clear skies) and no cloud
forms.  As soon as the sun hits the earth and
warms it up, you're good.  With a solid layer,
the sun bounces off the top of the layer and
it can persist into the day.  You need a hole
for the sun to peek through, and burn it open
with an increasing dewpoint spread.


[quote]What is the minimum dewpoint spread for night VFR?  Why?[/quote]

3 degrees C for 1000 AGL for dry adiabatic
lapse rate.  But watch the trend of the dewpoint
closely.


[quote]What can go wrong during a night VFR takeoff?
What techniques and exercises can improve this?[/quote]

The so-called exotic "Black Hole" effect, which
causes us old guys to snort.

As a takeoff technique, get on the AI ASAP with wings
level and 10 degrees nose up.  No turns until 500 AGL.

As a training exercise, learn to do a 0/0 takeoff.  They
used to teach them in the military (probably don't any
more).


[quote]What can go wrong during a night VFR landing?
What techniques and exercises can improve this?[/quote]

Low-timer are fooled by illusions and have difficulty
judging their height at night.  They are already prone
to pitch PIO's and this makes it almost a certainty,
which is terribly hard on the nose gear.  Wiping it off
is quite routine.  See photo above.

Learn to do a "glassy water" landing.  No sawing away
at the control column.  Set a pitch attitude and a power
setting that results in a gentle descent and let the
aircraft enter ground effect and flare on it's own.

Learn to land without the aircraft landing light.  Learn
to land without any lights at the airport.  All of these
will improve your night landings, as will simply more
of them, so you get used to the illusions.

Learn to do a 0/0 instrument landing.  Builds character,
it will save your life some day.

After a while, you won't give a shit - day or night, it's
all the same.  Aircraft has no eyes, it cannot tell the
difference.

[Chuck Ellsworth]

[size=6][color=#ff0000]Find an instructor who can teach you zero / zero takeoffs and landings and the so called black hole effect will not exist for you.[/color][/size]

[anofly]

While on that night cross country, keep an eye on the yard lights below you when they start to go hazy, or halo a bit etc. things are starting to fog in below you,often you can see it in car headlights on backroads, and  assuming you are in a part of the country where there are lights, and airports, its time to hurry up and get on the ground.......before it fogs right in..

[Chris]

With regards to zero/zero landings, am I correct to assume that it’s basically an instrument approach followed by a glassy water type landing? Or am I missing something? I’ve practiced zero/zero takeoffs which are easy enough, but that’s because you’re starting from a known position. Hard to get lined up with a runway you can’t see on approach.

[Colonel]

Yes.  A 0/0 landing requires vertical guidance -
traditionally an ILS or preferably GCA/PAR.

Traditionally only very expensive (long, wide)
runways are serviced by such equipment, but
these days, LPV's are everywhere, including
shorter runways.  Worst case, you run off the
end of a short runway after a 0/0 approach
and landing, which is a survivable crash -
no vertical, slow horizontal.

Better than the alternative.

[Colonel]

[quote]Find an instructor who can teach you zero / zero takeoffs[/quote]

Minor problem, Chuck:  like tailwheel/rudder skills,
these abilities have been bred out of the current
pilot population.

I would be very skeptical if you could find a single
instructor at any FTU in Canada that is experienced
at (and thus could teach) 0/0 takeoffs and landings.

FTU's and flight training in Canada are all about paper,
and keeping TC happy - not about building pilot skill
and knowledge.

I was lucky enough to have a grumpy old air force
instructor teach me 0/0 takeoffs and landings, and
black landings.  But, they're all gone.  Replaced by
button-pushing kids with product in their hair and
facebook selfies.

[anofly]

Fair enough, but dont do a zero zero landing in say Peteborough , when you could do it in say oshawa with a tower, or better yet , hamilton or pearson with a bigger runway, and staff to deal with your controlled crash., maybe even trucks... If you dont have enough fuel to get there, then do what the Colonel says....wherever you have to...

[Chuck Ellsworth]

Why would there be any possibility of a controlled crash?

[Rookie Pilot]

I've done black landings in training. No landing or interior lights. Wide runway lights were on but hardly mattered. A good exercise even to fly in the pattern with no interior lights. Plane amazingly does keep running. 


I had decent training all in all. I can't really complain too much. BUT I did seek it out and was rigorous to find and pay for instructors who put me through the wringer.  Crosswinds, IMC, upset recovery.  When I do approaches now I do them at near cruise speed, 120 knots, hand flying the ILS. Make it harder.


  I told them to do that the whole way through, PPL NIGHT CPL IFR, don't take it easy on me train me hard and well. I'll pay you well but work me out. Want to sweat through it. Paid more extra lessons, too, by my own choice.


Greater problem IMO, as with all of life, is willing to work hard and choose an attitude of excellence. Very rare -- among the students, or among anyone.


I've applied it to my business overcoming being a broke college dropout, through sheer hard work and commitment.  And I've made mistakes but tried to apply it to flying.


Most people simply don't value hard work. They want it all for free, with Mommy and Daddy paying. Entitlement.