Night Flying.

[LousyFisherman]

Thanks Guys,

During the day I can plan my route so there are places where I can land and at least survive if the engine quits.

However I am willing to bet that we have very different definitions of "decent emergency landing places".

Obviously these two are related.

The generally accepted definition of a accident that will result in no injuries is one where the forward or downward deaccelaeration is less than 9 Gee's. A light aircraft will deaccelaerate from 60 knots to 0 knots under a steady 9 Gee deacceleration in about 25 feet.

And math too.

Lots to think about here, I will have more questions later, need to review the trees vs water thread and then I will start a new thread about what constitutes a "decent" forced landing place so I don't hijack this one any further.

Your insights are greatly appreciated,

LF

[172PIC]

Just got my PPL ticket and starting my night rating next week - lots of good info here, thanks to all who posted.

As for the not flying night in a single thing, unfortunately I don't think those of us with an ATPL down the road in mind have much of a choice - I'm stretched for money as it is, renting a twin at $300 an hour to get those 25 xc hours is just not an option. But fortunately I'm in SW Ontario so lots of built up areas, lights and fields. Looks like I'll be sticking to this area for most of those 25 hours then.

I also bought a Garmin 296 a bit back which has terrain and obstacle warnings built in, I plan on having it on for every single night flight I do - not to be reliant on it for navigation, or use it as the primary tool to avoid terrain (new towers go up, databases can be off) but I'd rather catch that blinking in the corner of my eye warning me about the tower ahead with the lights out etc.

[Big Pistons Forever]

I (fortunately) am in a position where I can choose not to fly singles at night. Realistically a new PPL does not have that option, and night flight by a low time pilot is not an automatic death sentence. However there are undeniably higher risks at night. What I find sad is there seems to me to be many pilots who are flying around blissfully ignorant of the risks or things they could do to ameleorate them. Weather is the number one killer at night and the usual accident is inadvertant flight into the clouds which cannot be seen at night followed by spacial disorientation. Another frequent night accident is CFIT , usually on takeoff or landing caused by hitting obstacles around the field which are not visible at night. Fortunately the hardest thing to deal with, a suddden engine failure not directly caused by the actions /inactions of the pilot (carb ice, running out of gas, takeoff with a known fault etc); is the least likely to occur.
Bottom line; there are things you can do to lessen the risks

My 02 cents (for low time non instrument rated pilots)

1) Be extemely conservative with weather. There should be no cloud at all 2000 feet higher than your highest planned cruise altitude. Vis should be at least 15 mi with no precip of any kind. Temp/Dew point spread of at least 3 deg, at the time of the flight.

2) Fly high, 4500-5500 AGl or higher. This gives you more time and options in the event of a engine failure and more visibilty in flight.

3) Try to stay withing gliding distance of airports. Sometimes a few mild doglegs will keep an airport within reach for much of the flight

4) The most dangerous flight is one starting in the hour before sunset and continuing into dark . Fog is liable to suddenly form just after sunset particularly on clear nights

5) Always fly the VASI !

6) Get into the habit of checking the AI for the correct climb attitude right after liftoff and verify the aircraft is climbing with the VSI. There can be powerfull nose down illusions created, especially when takingoff towards an unlighted area. Many planes have crashed off the departure end of an airport after the pilot failed to realise he was not climbing.

[GoinNowhereFast]

All excellent advice, thanks BPF. One problem though, you do not want to cruise above 5000' because your vision starts to decrease due to mild hypoxia. If you live on higher land around Calgary, obviously you can bend that a bit, but keep in mind the reasons behind it.

[Big Pistons Forever]

All excellent advice, thanks BPF. One problem though, you do not want to cruise above 5000' because your vision starts to decrease due to mild hypoxia. If you live on higher land around Calgary, obviously you can bend that a bit, but keep in mind the reasons behind it.

The options for East bound flight are 3500 ft or 5500 ft. Personally I would go for the higher altitude even if it is above 5000.

[GoinNowhereFast]

There could be many reasons to choose 3500 or 5500, both are good altitudes. I would rule out 7500 and 9500 though.

[Guills]

As a low time (230 hours) pilot, I have a question regarding hypoxia for the older pilots here.

Quite frankly, I'm not a big fan of flying SE night VFR but I do have to do it sometimes. When I do, I usually try to fly at 9500' to get more visibility and more glide time if something bad happens.

I've never noticed any of the hypoxia symptoms and I am always on the lookout for them. I've flown some of these trips with instructors that also felt comfortable at 9500' and we've never noticed anything unusual, even vision-wise.

We all know the airplane flies the same at night or in clouds as it does on a clear day. Now, I think my body feels the same day or night at a given altitude. I've never had any problems at 10,000ft in the day.

On a side note, I've talked to my medical examiner about this and he said any symptoms of hypoxia (probably only vision related) would disappear instantly on descent and would most likely not be a problem.

So, for those of you with a lot more experience, what are your thoughts on the subject? Myself, I believe this is very dependant on your age, shape, etc. If your body lets you do it, why not? I feel more comfortable at 9500' at night with 2 airports in range.

[Cat Driver]

I can only speak from my own experience and state I can not recall having or being aware of any change in vision problems flying in the ten thousand feet regions day or night.

I do believe in the higher the better as far as safety goes though.

[5x5]

I never intended to say that anyone will definitely experience vision issues when flying higher. However, there is enough written by knowledgeable folk (see the eye article I linked to earlier) that I accept the fact it is a risk. The one thing about poorer vision, is it's not an on or off scenario, so how can you really know if there's any degradation? It's not that you can't see at all, you just won't see as well. As with any risk, there is no certainty it will occur, but being aware it could occur, I take steps to mitigate it.

One step is to descend more gradually so my eyes have more time to adjust. It doesn't impact my flight overall other than beginning the descent sooner so why not? The second thing is to insure that I avoid a long straight-in approach. And thirdly, I also make sure, using instrument backup, that I'm at least 100' high turning final. The last thing you want, especially if your night vision is slightly impaired is being low.

What's the worst that can happen if you're too high over the numbers - you go around in a nice, normal circuit pattern. You can establish distances and as much visual ground contact as possible in a nice, familiar environment. I've never heard of anyone running into something because they were too high.

Particularly at night, be even more willing to go around if everything isn't lining up just perfect for your landing.

[Cougar]

There are lots of good points here.

Our vision does deteriorate more quickly than we expect at night; our eyes function differently. In general, I agree with "the higher the better" when choosing a cruise altitude, and my typical "night VFR" is in the 11,500 - 12,500 range, and that even demands staying over the valleys sometimes.

Use this as an opening to try to learn YOUR personal needs. I've flown all day at 12,500 with no problems with anyone on board, month after month, and yet have had two cases where the workers in back suffered hypoxia as low as 6K - 10K. And, they were very young, and neither smoked! I was pretty surprised, to say the least.

[Big Pistons Forever]

5 X 5

I think this is a good example where reducing risk in one area of the flight, flying at lower altitudes to avoid risk of vision impairment, will increase risk in other areas, flying lower reduces the gliding range and time, reduces flight visibility, reduces radio range, etc. In my opinion the advantages of flying high outweigh the risks of potential vision issues. However most pilots are probably not aware of this aspect of night flying and it was worthwhile for you to mention it. Pilots should be mindfull of the symptoms of altitude related vision impairment, particularly at night.

On a related subject one of my pet peeves is improperly set cockpit lighting. The usual problem is the cockpit lights are set before the eyes have become night adjusted and therefore are too bright for most of the flight.

[MichaelP]

I tend to keep dimming the cockpit lights as the outside lighting is reduced.

It's difficult on the ground sometimes as there's floodlighting on the aerodrome, other aircraft taxying around with their landing/taxy lights on, and even vehicles at times.
On the last night flight I went on there was a Seneca in the runup, landing and taxy lights off. As a courtesy we turned our light off when it was likely to shine in the Seneca's direction.
Then a Malibu turboprop taxied out towards us... he was going to the other end of the field for testing and he had three bright taxy lights turned on in our direction and destroying the night vision we had by then built up.

Landing after this flight we taxied off on Charlie at Boundary Bay to be faced by a floodlight on the corner of the hangar. I had to stop and then creep forward squinting into this light.
I mentioned it to the aerodrome operator the next day, but then there's rules of how the new apron has to be floodlit!
I was assured that something would be done about it.

[Edelweiss air]

Wow! Awesome amount of information in this thread . Thanks a bunch everyone.

[AuxBatOn]

Re: Night Vision vs High Altitude

I did the baro chamber and experienced the symptoms of hypoxia. You should be able to get a decent warning. Tingling in the extremeties, so to speak, was my first symptom. During my chamber run, I think everybody had time to put their masks back on after their recognized their symptoms. Mind you, we were sprung loaded to experience the symptoms. If you have no issues during the day at a certain altitude, chances are you will be fine during the night, or at least, you will not turn into a funky chicken.

Now, talking about vision, at night at altitude. I can tell you with certitude that even at lower altitude (6000') you will lose color vision at night. It was quite a shock to me when the chamber stabilized at 6000'. I tought the color board was normal... Until they brought the altitude down to sea level, then it was obvious that I was missing a whole part of the color spectrum.

I always considered night flying as being in between vmc and imc. Therefore, I fly by looking at the instruments. More so than during the day in vmc (maybe not, I am a HUD cripple after all). Of course, looking outside is still required. But my control instruments are in the dash and not outside.

[Cougar]

It sure seems a few folks never got the lesson on lighting manners. There's nothing like a bright landing light or strobes from someone taxiing up to ruin your happy night vision.

I asked a friend to ride along once on his empty charter leg, just to see what symptoms I'd get without O2. It started at around 14,500 and kind of snuck up on me -- all I wanted to do was go to sleep. I had NO interest in the flight, the weather, the routing -- anything. Within minutes after that, the headache started.. a doozy. I would have done anything to fall asleep.

On the descent, both symptoms immediately went away.

On night surveys at high altitude, with two pilots, we each check the other's fingernails for color changes with a flashlight -- many people get the bluish tint at the base of each nail. We also ask each other silly questions and keep an eye on each other, just in case the oxygen system malfuntions. It's harder to catch visual signs at night.

So, it's handy to at least be aware that my most obvious symptom is a dull, yet splitting headache.

Oh wait, that's the copilot...

[Big Pistons Forever]

So, it's handy to at least be aware that my most obvious symptom is a dull, yet splitting headache.

Oh wait, that's the copilot...

Coug you are anoxic ! The headache is from the lack of oxygen,... the loud and annoying buzzing noise in your headset... is from your copilot...better get on 100 % O2 stat..

[tommywcom]

Night flying - I was simply taught to follow the highways / lit roads going from point A to point B. You are guaranteed terrain clearance. And if the engine quits, there is a place to put the plane down assuming power lines don't get in the way. I thought it worked out pretty well - at least it gave me enough confidence to not have to be obssesed about the engine quitting every single minute.

As for bright light destroying night vision - once again I was taught to just close your dominant eye when there is a bright light so at least you could keep going afterwards with one eye. Hopefully depth perception is not too critical of a need at the time ...

[MichaelP]

Flying one leg too many to Penticton in the Cessna 152 as the Sun descended to the horizon I tended to do as above, close one eye and have it ready for the descent into the darkened valley below should the engine fail.
I also calculated my glide, would I make it to Nelson? to Castlegar? into Penticton itself... I planned for the engine failure so there would be no surprise.

Night flying does not have to be official, just try mountain valley flying well before the Sun actually sets. You won't see the into Sun wall...

I once was on my way to Columbia... It was getting dark.
The aeroplane was unstable and would roll off and the turn and slip was all I had... I decided the lightless mountains ahead were too uncomfortable and turned for Sacramento instead...
I had only 20 odd NM to go but it was too uneasy for me.

Later spades were added to the ailerons, the roll rate improved enormously but strangely the re rig made the aeroplane easier to keep level.

I suppose the conclusion is that you should have everything in your favour flying at night and if you feel at all uncomfortable, divert.

[desert goat]

So where can one go to do a Baro chamber run, and how much does it cost to do this typically?

[100LL81]

I am a 200 hour wonder just finishing my Multi and IFR, I cringe at the thought of doing anymore single engine night flying but obviously I need my hours for my ATPL. I have saved these hours for after I got my multi so I could do the night in a twin, however I have learned that my flight school does not rent the twin for solo flight and told me most places don't. So does anybody know of any place in alberta that rent twins?

Great topic BTW. It is just crazy that TC requires the broke ass students to do SE night hours (well they don't make us but they damn well know most students cannot afford to do it in a twin)

[MichaelP]

I have flown the English Channel many times in daytime.
There's not much difference between day and night in a single engined aeroplane when over a large body of water.

We all risk, but we do everything we can to reduce the risk except stay on the ground in the first place!

Night flying in a single engined aeroplane has a greater risk of a poor outcome should the engine fail.
But should the engine fail at night more often than during the day???

One thing about a night preflight inspection is that it is usually a much better inspection than one done in the day time.
A bright torch light focusses your attention on what is there and only what is there..
Shining a light into the engine compartment at night is far more revealing than a glance on a bright sunny day.

Do we not fly over the mountains in day time in single engine aeroplanes? How risky is that?

I would not advocate flying the mountains at night even in a light twin... the single engine ceiling is often below the mountain tops
IFR likewise in a single is a state of emergency, and likewise in the light twin there's additional risk.

But we take reasonable risks based on the aircraft's condition, our training and currency, and with as many outs as possible.

[5x5]

An engine failure at night is no more likely at night than in the day, but the likelihood of a poor outcome at night is much greater. But the engine failure is not the significant risk at night. The significant risks come as a result of vision issues.

Humans do not see well in the dark - plain and simple. The darker it is - no moon, overcast, isolated area with little or no ground lights - the worse/less we are able to see. Add to that illusions, weather issues and we really see poorly. Most fatal accidents at night occur in the landing or departure phase.

But all the risks regardless of phase of flight need to be known so the pilot can take steps to mitigate that risk through good planning and excellent decision making. And that applies for any flight of any kind, night or day.