How to approach in VFR?

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21

The Garmin was a substitution for the flood of information available in todays GA cockpits. The general problem - I think - is that many pilots, shortly after early student status, stop thinking and rely on various digital aids. I’ve seen Cessna pilots on Youtube that overload their cockpit with iPad here, FIS there, TIS, Aspen PFD, digital checklists, Smartphone auto updating various en route ATIS, etc. With that huge amount of input that is meant to increase situational awareness and provide additional safety they seem to forget the point of easy mental maths, rules of thumbs. They provide themselves with a Top Of Descent from an altitude delta of 5000 ft in their fancy ipad app that can even calculate a correction angle and - heck - a take off flaps setting for your C172. That’s basic knowledge.

I think the priorities have become wrong.

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22

To add to the good advice above.

GA

If no ATC broadcast intentions.

Descend to 1000 ft above runway on the dead side of the circuit being flown and join upwind

Fly downwide, broardcast RegNo Downwind when level with the upwind end of the runway

I turn onto base when the threshold is in my 5 or 7 O’Clock position. Broardcast position ie RegNo On Base

Turn onto final 700 ft above runway threshold broadcast RegNo On Final

Where the PAPI lights are or would be is your aiming point, keep this in a constant position in your windscreen until you cross the threshold.

All the while on Final maintain a constant velocity and descent rate by attitude and engine power.

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23

Yes, best results are achieved by ground speed * 5, but as a rule of thumb it also works with indicated airspeed. The difference between these two increase with altitude and deviation from standard atmosphere. And of course, ground speed factors in the wind, so, if you‘re approaching with 100 kt indicated and you know that the tower reports a 20 kt headwind, so it would be about 5 * (100-20) ~ 400 fpm.

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24

And the rest would be „eyes open“

You know how a runway has to look like, you have natural 3D vision with a pretty good framerate and no stutters. There‘s really no VSI required on a visual final. ^^

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25

It really doesn’t matter if you are flying a 3 degree versus a 2 degree slope for example from an engine failure perspective, in neither case are you gonna make it to the runway and in both cases you’ll need to land more or less straight ahead, making shallow turns to avoid obstacles. No aircraft will be able to continue to the runway when the approach is flown on-speed, on a 3 degree glideslope in landing configuration. You need to be really, really hot and high and in clean configuration (i.e. glide-in approach) to make it to the runway with an engine failure.

Be aware that the drag modelling in MSFS is hideous and the real aircraft has way more drag with a windmilling propeller and therefore less glide range.

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26

There is a lot of good advice here. When I trained, my instructor taught me how to pick a spot on the runway and place it on the windshield. (it was a long time before I landed at a field that had VASI or anything like it). :slight_smile:

Once you have the proper speed and settings (flaps, etc.) for your aircraft, keep your aiming point in the same spot:

  • If it doesn’t move, you’re on the proper GS
  • If it moves toward you, you’re too high - reduce power
  • If it moves away from you, you’re too low - add power
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27

Exactly! :blush:

The only thing is the power = glidepath and pitch = speed technique is a little out dated, it is very black and white and might work well on a Cessna but not on anything bigger with more inertia and slower power / thrust response time, when I was a flight instructor 5+ years ago we already started to shift away from that philosophy and approach it more as a combination of the two.

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28

Well, and to be fair I never at any time mentioned ANY angle of glideslope.
My point is that - unless specified or for weather considerations - fly the SAME glideslope for every landing. Because this helps to build up consistency.

And when I mentioned flying too low, by definition, flying too low IS flying too low! In my example I was clearly indicating flying low enough to risk hitting obstacles.

Regarding your final point. Yes, the current state of the flight dynamics in MSFS 2020 leaves a lot to be desired. But in the meantime - and in the hope that this is improved - there is nothing to stop us all, should we feel the inclination, from learning and honing as realistic a flying ‘style’ as possible.

At no point in my post did I promote anything I wrote as correct or definitive.
Indeed I twice clearly used the phrase “I have found”.
I also stated that these are “my thoughts”.
My post was merely a reply to a request for help. And this I provided in a clearly anecdotal way!

I have made many, many posts within these forums. Should you look, you will find that often I make the point that readers should not take anything I or anyone else says at face value. I then usually go on to suggest that the reader does his or her own research [in these forums and beyond}.
On this occasion I did not.
Your post reminds me that I should have.

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29

Sure, flying lower / shallower is never a good thing, the primary concern being obstacle / terrain clearance. You mentioned that flying a shallow approach, you might end up landing short with an engine failure. My point being, unless the engine fails over the threshold you will almost certainly end up short of the runway, when flying the approach using the correct glidepath, on-speed and in landing configuration there is too much drag and not enough kinetic energy to extend the glide distance and make it to the runway.

Only reason I would fly anything different than a 3 degree glidepath is for terrain, obstacles (steeper glidepath not shallower). Only condition I can think of when glidepath would be shallower than 3 degrees is when flying a RNP approach using Baro-VNAV with a cold temperature, but that’s not relevant here. If you are flying VFR and have to stay low for weather, you could descent later and still fly a 3 degree glidepath?

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30

This makes sense, + I did my flight-training in the early 70’s…

In those days, opposite the threshold, we would pull to power off (152s and 172s), add 10 degrees flaps, hold the nose up until the speed dropped to 70 then release back pressure to maintain that speed all the way to final. If all went well, we never touched the throttle again.

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31

Good tips!

32

At the world map if you add the airport/runway you want to practice as the TO fields and leave FROM fields blank it will spawn you on final approach.

The plane is not well set up .But after a couple tries you can easily practice landings over and over again.

Be nice to others and turn off multiplayer when you do this though.

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33

It is worth noting that the 3 degree glide slope is optimal for airliners ILS approaches but there are a number of reasons that might justify being slightly higher in a VFR approach in a light plane including obstacles on final.

There are however very few good reasons to be intentionally below 3 degrees glideslope. Scud running under a very low ceiling probably is the only one that comes to mind and that is illegal unless you are both certified for it and have had recent low level PIC time/check ride.

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34

3 degrees is standard, not only for IFR approaches, VFR approaches should also be flown 3 degree if possible. The landing distance from the aircraft POH is also based on a 3 degree glidepath, cross the threshold at 50 ft, start flare 300 m after passing the threshold, flare, touchdown and brake. If not possible due to terrain or obstacles, sure you need to fly a steeper approach but that is not only true for VFR, an IFR approach would also be modified with a steeper slope in that situation. The obstacle identification surface is normally set to provide sufficient obstacle clearance for a 3 degree glidepath unless stated otherwise.

So there are no good reasons to fly a shallower approach, even when you are flying low due to clouds, you can start descent later, still following a 3 degree glide? Only situation I can think of where the glidepath is shallower than 3 degrees would be a RNP approach using Baro-VNAV without temperature compensation on a cold day.

Never heard about the “low level scud running” certificate you are speaking of? In Europe we have the SERA-VMC minima we need to adhere to + minimum flight altitude above ground of 500 ft outside of built-up areas. When flying in class F or G airspace you’ll need to be “clear of clouds” so technically you can fly VFR at 500 ft above ground while avoiding built-up areas with the ceiling at 501 ft. But there is no certificate or hour requirement for something like that.

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35

the pitch-power coupling is a good theory to keep in mind what is important: altitute is speed is life. If your engine fails you won’t make it to the runway by pulling the nose up, nor will you make a safe (crash) landing this way. But as long as that fan blows cool air at you pitch and power goes hand in hand. if you need to push down you pull the throttle back.

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36

I, too, first trained in the 70’s (1978), and when I was taught pattern work in the 152, I was told to remain within power-off gliding distance after reaching midfield downwind. And my training included how to land precisely on runways (or grass strips) that had no markings or VASI.

The key to the precise approach was the aim point technique. That magic spot-on-the-windshield trick works for any glide slope angle. If you keep your aim point stabilized in that spot, then you’re automatically going to fly whatever glide slope angle is required to crash into that spot on the ground unless you flare.

Think of it this way. VASI / PAPI guidance has you typically maintain a 3 degree glide slope by keeping two reds and two whites. You typically approach in a level attitude while seeing all red lights. At the point where you see two reds and two whites, you begin and maintain a 3 degree descent. If you keep two reds and two whites or use them as your aim point and keep them in the magic windshield spot, you will crash into the runway right on top of them unless you flare.

So there is nothing supernatural about a VASI, or about using the big runway markings beside them as your aim point. Those do indeed give you a built-in margin of error during landing, but I feel that they are just a crutch during initial, small plane training. They are later a rule of thumb for flying high performance aircraft and airliners, but they are not needed as much – or used as much – for advanced pilots flying in VMC and trying to land on the numbers, or land with a much higher angle of descent for landing on a short runway over obstacles, etc.

SO HOW TO DO A LONG VMC APPROACH WITHOUT A VASI?
In small aircraft flying, you’ll generally be joining a pattern when landing at an airport. If it is uncontrolled and unfamiliar, or just a grass field, you should probably overfly the airport at midfield, 500 feet above the traffic pattern altitude and take a look at the windsock / triangle, the runway condition, birds, dogs, children, other aircraft taxiing, etc. Then enter the appropriate downwind (left or right) on the other side and land.

If you are making a long, straight-in approach, establish yourself at the published Traffic Pattern Altitude and fly level toward the runway. This is where the Aim Point and the Magic Windshield Spot come into play.

As your aim point approaches the magic spot, you want to get configured for landing. Slow to approach speed, and begin your descent when the aim point reaches the spot. In a Cessna 152 or 172, aim for a 500 fpm descent and add flaps as you go so that you touch down around 60-65 knots.

In general, unless landing ON the numbers, you should pull power as you cross the threshold, look far forward to the end of the runway, flare as appropriate, hold it off until it slows down, and let the aircraft settle until it’s ready to touch down.

PITCH VERSUS THROTTLE FOR SPEED AND DESCENT RATE
As many have said here, the old school “pitch for speed, throttle for descent rate” has been argued for decades. Nowadays, it is taught that the two are related and controlled together. And you see most new pilots landing a 152 like a jet, with abnormally high speeds and jet-like approach profiles.

My position on this is that new pilots should be taught to remain within power-off gliding distance while in the pattern. And they should still be taught – and have a lot of fun practicing – how to precisely land with the power off when abeam the numbers.

ALL pilots – no matter their knowledge or experience – will instantly be thrust into a challenge where they had better understand that PITCH = AIRSPEED and THROTTLE = NOTHING!!!

I firmly believe that my instructor – who was a Delta copilot by the way – taught it the way she did because of that safety aspect. She felt that if your engine quits an any time, you can not only land safely, but you can also still land precisely. “Fly the airplane! Don’t let it fly you!” She made me a master of speed control using pitch during power-off landings, an expert at short approaches and slipping for faster descents, and greasing a landing precisely on the numbers.

Those are some things the sim allows you to practice and play with even right now. And so what if they change the flight behavior a little bit. Pretend you’re a test pilot and have to tame the beast anyway!

Happy flying,

Yeti

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37

Depending on the aircraft type maybe, I’ve never heard of this technique before. On the aircraft I learned to fly and later taught others how to fly you won’t even make it to the runway from pattern altitude when cutting the power abeam the threshold unless flying the downwind very close to the runway. Many airports here have prescribed tracks to fly in the circuit so you can’t always choose were to fly your downwind. Only times we used the numbers was for practicing precision landings, and for simulating engine failure (aim for 300 m, then full flaps and aim for the beginning) otherwise aiming point markers always.

This is not related to the technique used, in both cases speed control is the most important parameter and speed should be 1.3 x stall speed in both situations. The technique itself is not really any different, the explanation is. When viewing it black and white, power = glidepath, pitch = speed you’ll end up with students being below path but otherwise on-speed adding power, speed increases, they then pitch-up to maintain speed which brings them (hopefully) on the correct glidepath, while all he/she had to do is add power and simultaneously pitch-up to maintain speed, also when being on path but slightly high on speed, I don’t think you should pitch-up and destabilise yourself while reducing power slightly while maintaining the correct glidepath would do the trick. Therefore the modern approach makes more sense in my opinion over the black-and-white approach, in essence power still controls glidepath and pitch still controls speed. The old black-and-white approach is useless on anything with low mounted jet engines, or anything bigger than a Cessna with more inertia for that matter.

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38

I absolutely agree with this statement – however…

I was initially trained – as have many US pilots over 50? – on a Cessna 152. It has a huge glide ratio – something like 10-1. Best glide is like 74 knots? That’s very easy to attain and hold when losing power.

I was wondering how pattern work was taught in other countries. It seems like there has never been a de facto standardization about techniques or aircraft like there has been here. Of course, standardization breeds rigidity and limited points of view, but it also can decrease confusion. I think the main thing standardization does is to allow consistent training and documentation. Rod Machado appeals to a lot of new pilots, and he’s been teaching the same things for decades.

Oh, well, my main point was that a pilot should be good at pattern work and understand how to approach unfamiliar airports under VFR. I remember how hard it was to even find an airport in the distance, how to enter a downwind at the proper distance from the runway, and especially how to set up a good straight-in approach and when to start descending.

The tips in my previous post was how – and why – I was taught, and they have worked for me ever since. They are good principles for a pilot such as the OP to try. And in this day of automation, if you have an engine failure and must instantly find a good landing place, set up a visual-only approach, and put it down precisely over some obstacles, I know the way I was taught works!

Did I mention that my instructor’s husband had also been a flight instructor that was killed when his student froze during takeoff and mushed them into some power lines? That woman was constantly pulling the power out of the blue, and I had better already know what field I was going to land in, instantly establish best glide, and begin an appropriate pattern / approach for landing, including any crosswind!! To say the least, my training was intense!

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39

Awesome explanations, and I will never forget “fly the airplane, don’t let it fly you”.
Fly even when you are not flying.

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40

I think pattern work is quite standardised, but maybe not between both sides of the pond :joy:. I know UK is slightly different as well, with different entry and leaving procedures. Otherwise the keypoints are the same:

  • Entry at 1000 ft AAL, 90 degrees mid-downwind (left-hand standard).
  • Downwind distance determined by wing striping (little step on the Cessna).
  • Turn to base when threshold is 45 degrees behind the wing.
  • Descend on base as to start the final leg from minimum 300 ft AAL (3 degree glidepath).
  • Pitch = speed, path = power (kind of)
  • Aim towards aiming points (300 m after threshold)
  • Cross threshold at 50 ft, start flare over aiming points, touchdown and brake.

Don’t know how much this differs from US? Locally it might differ of course, some airports have prescribed tracks and markers to use so you are not that flexible in choosing were and how to fly the pattern.

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