4 Hurt in Plane Crash at Brampton

[dpm]

Must use vasi at night. 2 white, 2 red all the way down, will keep you safe. Though I'm not sure how dark it would have been to need that, or what Brampton has for vasi lights.

Question from someone working on their night rating:

How adamantly do you follow the VASI/PAPIs? The reason I ask is that any power-off approach I fly, even with flaps up, is a much steeper approach angle than the 3 degrees the lights would give you. I generally don’t see 2 red/2 white until I’m at the threshold. I’ve tried to follow the PAPIs and it feels awful – power on, super long final, and zero chance of making the field if the engine quits. That last point is what really bugs me, because at my airport if you can’t make the field you’re guaranteed to have a bad time.

I don't usually drag it in low following a PAPI/VASI at night, but you can still use it as a warning to make sure you're not too low.

[dpm]

If you’re comfortable flying a single engine aircraft at night at all, it’s silly to start worrying about making “the field” because of an engine failure in the last minute of a two hour flight.

Fair enough, but that's not the only reason people choose steeper approach paths. There's also the benefit (especially at night) of having a bit more room between you and the (maybe obscured) obstacles under you in case you hit some wind sheet, downdrafts, etc—it makes it less nerve-wracking pushing the nose down to get your speed back up.

D

[photofly]

And it can leave you with a prodigious rate of descent over a black infield and a really horrible round out and flare with very little depth perception over the runway, and then a really hard landing.

Pilot’s choice of risk, as ever.

[dpm]

And it can leave you with a prodigious rate of descent over a black infield and a really horrible round out and flare with very little depth perception over the runway, and then a really hard landing.Pilot’s choice of risk, as ever.

In a small plane like a Cherokee or 172, no—a 6 degree glidepath is as natural as a 3 degree glidepath for a larger, slicker plane, and results in about the same amount of excess energy (relatively speaking) to disperse after you cross the fence. When we force these small, draggy planes onto 3° glidepaths (e.g. for an ILS or LPV approach), we're flying something designed for a totally different kind of plane, and end up dragging them in with high power and/or dangerously-low speed. It makes no sense to try to fly a Cherokee the way you fly a Dash-8 or A-320, except that we need to conform to the same approach procedures when IFR.

[photofly]

When we force these small, draggy planes onto 3° glidepaths (e.g. for an ILS or LPV approach), we're flying something designed for a totally different kind of plane, and end up dragging them in with high power and/or dangerously-low speed. It makes no sense to try to fly a Cherokee the way you fly a Dash-8 or A-320, except that we need to conform to the same approach procedures when IFR.

We never force a small plane to do anything, we're pilots and we simply fly them in the manner we desire. If it's safe to follow a VASI it for an instrument approach in a 172, it doesn't become more dangerous to do it VFR at night. We simply have the flexibility to fly a steeper approach if it's appropriate under the circumstances. Whether you find an instrument approach gradient comfortable is all in your head; you can make it second nature with practice, if you want. I promise you, the aircraft itself doesn't have an opinion either way.

Like I said, the pilot chooses whatever he or she wants at the time.

[CpnCrunch]

I'm with dpm...I prefer a steeper glideslope. The PAPI only guarantees clearance for a given distance/angle. If you have an offset final approach with obstacles, that adds to the risk. With an instrument approach there is more obstacle clearance. Flying VFR at night there are many runways that have no instrument approaches due to obstacles.

[photofly]

The PAPI only guarantees clearance for a given distance/angle.

I fully support your right to fly any approach you like, day or night, but I’d like to hear why and specifically where you think following the full instrument approach guarantees you obstacle clearance that the PAPI doesn’t. A specific example airport and approach plate would really help me follow your point.

[HiFlyChick]

I think the steeper approach path in something like a C172 is the better option if you're comfortable with the runway - it's longer and/or it's your home airport and you're used to the approach. Two factors to consider, though, is that if you're approaching steeply, you should be sure you're comfortable with doing full slips, since you've already used up the option of full flaps (I presume) or reducing power. The other thing is that at this time of year, you really don't want to be in the situation where you need to pull the power back to idle and shock cool the engine.

If you're doing the 3 deg path in a C172, maybe only use a bit of flap until short final(can't recall the numbers for a 172 - been a while). I keep hearing discussions about stabilized approaches and the like, and that's fine in principle, but for people not in a transport category aircraft, even in a light twin, having full flap from the FAF on is just not realistic. When your flaps are like big ol' barn doors, and it practically takes full power just to maintain level with full flap, why not wait on the last bit of flap until short final? Where on final really depends on your experience level in the situation (i.e. amount of time at night,in the aircraft, at the airport, whatever).

I think where people really get in trouble is when they see someone who is much more experienced doing something a certain way (i.e. not the way we learned in flight school) and they start trying to do the same thing without their judgement or hands and feet skills being developed enough

[HiFlyChick]

The PAPI only guarantees clearance for a given distance/angle.

I fully support your right to fly any approach you like, day or night, but I’d like to hear why and specifically where you think following the full instrument approach guarantees you obstacle clearance that the PAPI doesn’t. A specific example airport and approach plate would really help me follow your point.

I get what he is trying to say - just that the instrument approach is well defined on the plate, while the PAPI/VASI have limits that are not as well known. I say that because obviously there are certain limits outside which they no longer provide obstacle clearance (distance back, angle off), but darned if I can recall what those numbers are... For those of us that are absent minded, the comfort of an approach plate is that the numbers are all right there in front of you with no memory items required

[photofly]

I get what he is trying to say - just that the instrument approach is well defined on the plate, while the PAPI/VASI have limits that are not as well known.

I really don’t get what he’s trying to say. The AIM says

At a certified airport, aircraft following the on-slope signal are provided with safe obstruction clearance to a minimum of 6° on either side of the extended runway centreline out to 7.5 km (4.1 NM) from the runway threshold. Newly certified airports are commonly protected out to 8° on each side of the extended runway centreline. Exceptions will be noted in the CFS. Descent using VASIS should not be initiated until the aircraft is visually aligned with the runway centreline. ..

...At some aerodromes, particularly in mountainous regions, a limitation is established as a PAPI useable distance from the threshold and is published in the CFS. The PAPI signal is not to be used until within that specified distance.

So, if in mountainous regions, let’s plan ahead, and read the CFS. And, of course. we’re discussing flying at night, so you even have the CFS with you, don’t you

In most cases the PAPI or VASI will coincide with the instrument approach to the same runway; if not, it’s noted on the plate. I’d still like to see an example of somewhere where following the approach slope indicator gives you an unsafe approach. If it’s unsafe, why is it there?

[rookiepilot]

What's really idiotic is how (I think) it's a good idea, at night at unfamiliar airports in hilly terrain, is to insist on an IFR approach (assuming qualified), even in VFR .

I'm told this is stupid. I think I'll continue to decide for myself rather than hit something.

[CpnCrunch]

I really don’t get what he’s trying to say. The AIM says

I think you've just made my point for me. 6 degrees isn't a lot, if the approach is offset and there are obstacles, and no instrument approach (presumably due to those reasons). I'm pretty sure you'll never get an instrument approach in cases like that, but feel free to prove me wrong.

[photofly]

I really don’t get what he’s trying to say. The AIM says

I think you've just made my point for me. 6 degrees isn't a lot, if the approach is offset and there are obstacles, and no instrument approach (presumably due to those reasons). I'm pretty sure you'll never get an instrument approach in cases like that, but feel free to prove me wrong.

What do you mean by "if the approach is offset"? Why would there be a VASI or PAPI installed if only an offset approach is safe? Is the approach into Brampton offset for some reason while the VASI or PAPI isn't? Perhaps if there's a PAPI there it's simply a trick to lure unsuspecting pilots to fly into trees, when they should have been flying a special safer but secret and uncharted "offset" approach. Who can say.

It seems straightforward to me. If there's a VASI or a PAPI installed, it's safe to follow. It gives you visual guidance along a constant angle approach right down to the ground that ensures terrain clearance. If you want to ignore the visual aids and fly a steeper approach instead, you're welcome to. I really don't know why you want to make this so complicated.

[Big Pistons Forever]

What's really idiotic is how (I think) it's a good idea, at night at unfamiliar airports in hilly terrain, is to insist on an IFR approach (assuming qualified), even in VFR .

I'm told this is stupid. I think I'll continue to decide for myself rather than hit something.

Who is telling you this ?

[photofly]

I think you've just made my point for me. 6 degrees isn't a lot,

6 degrees is more than double the full scale deflection on a typical ILS, for comparison. If you have trouble tracking a visual approach well within 6 degrees of the centreline, night or day, some practice might be in order, don't you think?

[Boney]

At night, fly an approach even if its VFR. It will at least give you obstacle clearances. Don't forget to temperature correct the crossing altitudes as you will be lower than indicated when its below 0 Degrees.

If you have lights below you, go to go. If not, better ensure you are at the right obstacle clearing altitudes.

Cheers.

[rookiepilot]

What's really idiotic is how (I think) it's a good idea, at night at unfamiliar airports in hilly terrain, is to insist on an IFR approach (assuming qualified), even in VFR .

I'm told this is stupid. I think I'll continue to decide for myself rather than hit something.

Who is telling you this ?

Right here.

[dpm]

Yes, I'm comfortable flying a 3° glide slope down an ILS or LPV, just like I'm capable of making my Cherokee cruise at 70 KIAS instead of 90–110 KIAS, but in both cases, I'm outside the optimal design envelope for my plane—in the first case, I'm running my engine at a non-trivial power setting to keep my plane on such a flat glide path. My point was just that the 3° glide path is optimised for bigger/faster planes, not for little single-engine/fixed-gear 160 HP planes like mine. We can fly them that way—and we do all the time on ILS approaches—but we're flying them well outside their ideal glide configuration, so why do it the times when we don't have to?

What I like about a 6° glide path, especially at night, is that I'm 2× as far above the landing zone elevation (and possibly relatively more than that above any obstacles) than I would be on a 3° glide path. That's a nice little insurance policy to carry down to the runway with me. More realistically, I don't usually fly a continuous descent, but level out a bit early at circuit altitude until I'm relatively close to the runway, then glide down from there. That lets me avoid the black hole effect when there is no PAPI/VASI, and to use the PAPI/VASI as redundant safety info (rather than the sole source of glide path info) when there is one. Win-win.

[photofly]

I’m running my engine at a non-trivial power setting to keep my plane on such a flat glide path.

Oh my gosh. A non-trivial power setting!? How truly awful. We should definitely strive to avoid “non-trivial power settings” to keep an airplane where we want it, shouldn’t we?

Why might we want to do that when we don’t absolutely have to? Because if we do, there’s a nice visual approach slope indicator that ensures terrain clearance and avoids many of the hazards associated with landing at an unfamiliar airport at night.

Which I think is where we came in.

[CpnCrunch]

6 degrees is more than double the full scale deflection on a typical ILS, for comparison. If you have trouble tracking a visual approach well within 6 degrees of the centreline, night or day, some practice might be in order, don't you think?

An ILS gives you an accurate horizontal indicator that you can follow. If you read my post, you'll see I was talking about an offset approach, e.g. at Nanaimo. If you approach on the VASI on runway centreline at a 3.5 degree glideslope, you'll get pretty close to hitting something there. If you're slightly left of centreline you'll definitely hit something. Hence the 10 degrees right offset, which you don't have any indication of (other than knowing the airport and looking for the obstacle lights).

Apart from that there's the problem of downdrafts...Three Hills and Duncan come to mind, they generally have downdrafts on short final if you're low, due to the terrain. If you come in at a shallow angle and there's a strong wind, you'll probably hit a downdraft. During the day it's not really a big deal, but I'm not sure you'd really want that at night.