Touchdown point

[JamesG]

I wonder if anyone can confirm where students are taught to aim for as their touchdown point? e.g. on the numbers, 1/3 in etc.

There is a thread on the Private Flying forum about why people land long and this information would be very helpful.

[Tail Plane]

I always teach students to aim for the threshold. That way, by the time they've held off and floated a bit they'll touch down just beyond the numbers and there will still be plenty of runway left to stop.

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You Have Control!

[Noggin]

On the basis that runway behind you is of no use at all, where else should you land but the threshold ? If you train off large runways, teaching people to land well up becomes habit forming, don't do it, until they have mastered landing in the correct place.

[Capt Crash]

At cambridge we have a good long runway, I still ensure that my students can land in the minimum distance possible. We have shorter grass strips avaiable to assist with this technique.

However, on PFL training you select an aiming point 1/3 of the way in the field and use flap (and side slip but not in C152s) to bring the aiming point nearer the start of the field.

I have found that some students add 5 knots on the approach speed for mum, and then maybe another 5 knots because it is windy. This means they will never pull of a short landing. Before you know it you will be touching down at 90 knots!!

[NIMBUS]

Don't forget that where you AIM for is actually the point where you flare, not touch down! Subtle difference.
'Aim' for a point 500ft-600ft before the spot where you want to put the wheels.
Don't know about Euro./CAA, but the FAA commercial training is hot on precision landings, and really teaches you to put the wheels exactly where you want them.

[dragchute]

Landing distances are determined on the basis of a threshold crossing height of fifty feet. Given a three to six degree glide path, the latter being more appropriate for light training aircraft, touch-down will occur somewhere near five hundred feet in from the threshold.
Down here in OZ the fifty feet threshold crossing height is required to clear dead trees, single strand telephone wires, ant hills, barbed wire fences and all the other paraphernalia associated with an 'outback' airstrip. Some of the city runways are equally as challenging with delivery vans and the like crossing on roads in the undershoot.
Why teach a student to land on the threshold if you must ultimately re-train him/her to land properly in a later sequence. If the runway is not long enough to touch-and-go without planting on the threshold one must question the wisdom and the legality of conducting a touch-and-go.
Sure, the runway behind is of no further use, but the runway ahead would look mighty good if you were hanging from a strand of wire 100 metres short of the threshold!


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dragchute
email: [email protected]

[Vigilant Driver]

Most regional UK fields have PAPIs or VASIs so if you teach your student to fly these then he/she will round in the right place. Agreed that without these or from a flapless (flat) approach you need to use the threshold as your aiming point.

Your actual touch down point should be as far away from the round point as possible. The best touchdowns come from trying to keep the aircraft flying as long as possible, even in a trike configured undercarriage. Alas some pilots don't do this and end up in the accident reports with broken nose gear.

Vigi

[A and C]

Capt Crash has hit the nail on the head a lot of low time pilots fly the aproach to fast the speed should be 1.3Vs ,most flying clubs then round this up to the next eazy to remember number the low time pilot then adds his "safety margin" and a bit for the crosswind and the gust and because the aircraft is heavy so we now have a C172 with a 80KT aproach speed .

Now it realy gets interesting as the guy trys to touch down the aircraft wants to keep flying and the end of the runway is coming up fast so the guy trys to force the aircraft down it bounces up and the next thing we are into is a PIO two or three cycles of this and the nose gear gives way and the whole plot slithers to a to a stop with £10,000 of damage.

[JamesG]

Thanks for your very helpful responses.

The picture that I am forming is that there is good reason to teach students to land a little into the field initially (i.e. if the engine quits, the landing is made), but that they need to develop more control as their flying progresses and they wish to land in less forgiving fields. Possibly this includes steeper approaches and certainly tighter airspeed control.

I use 1.3vs as my final approach speed stabilised between 2-300'(63.7 kias with full flap on the PA28 I fly - rounded up to 65kias due to fortysomething eyesight!) and find that this is very comfortable. If there are more than slight controllability issues due to gusts etc., then I have chosen the wrong day to fly!

Thanks again for your kind assistance.

[dragchute]

James G,
Speed control IS most important and your adherence to an approach speed of 1.3Vs is sound policy. Some years ago I operated Cessna 180 types into short fields (not really fields but claypans, roads, beaches or sometimes just a clear patch of ground). The approach speed was 1.1Vs as dictated in the ‘Precautionary Landing technique of our SOP’s (40 knots for a Vs of 36 knots in the landing configuration). The approach was stabilized with attitude and trim at precisely forty knots, and vigorous throttle application used to control the glide path to hit the aiming point. Prior to touch downpower was reduced to idle and full back stick applied for a firm three-point landing.(Getting out was usually another challenge – particularly with obstacles).
I do not suggest for one minute you or any other reader adopts this low speed approach technique. The point I make is that since 1.1Vs works (at least I got away with it on many occasions) then 1.3Vs must be perfectly safe with no requirement to increase for the ‘mum and the kids’ factor.


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dragchute
email: [email protected]

[grade_3]

G'day all,

I think an important consideration that should be taken into account is windshear on finals or a possible partial (or full) engine failure scenario (as JamesG noted a post or 2 above).

In either of the above situations, it really can save your bacon to be aiming about 250m (or 1/3 into the field, whichever is the lessor) rather than aiming straight at the threshold.

This, of course, depends on where you are operating from.

The school I work for is based at a large radar-controlled airfield with a 2,000m runway. In this location I've found pilots that fly an approach aiming at the threshold, w/flaps 40 (on a 172N) and 2200 RPM, seeming oblivious to the fact that if the engine decides to stop working they're going to lob into the sports field short of the runway.

For a short field landing, the method I'm most familiar with is to aim 1/3 into the field, close the throttle at 50ft (or once obstacles are cleared), fly down and land. It's the method given in the POH's and, whilst it may not deliver *really* short landings, most PPL's are able to get it consistently correct and land safely within the distances given in the POH.

Fly the numbers, read your POH and, above all, keep current.

Cheers,

Grade 3

[Capt Crash]

I think that aiming 1/3 of the way in the runways because you may have an engine failure is misguided. It is SOOOO unlikely that your engine is going to fail at or about idle power. It is under the most stress on a go-around, with an engine failure at this point you will be grateful of any runway ahead of you!

Just my thoughts.

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WHOOP WHOOP
PULL UP!!!!!!

[This message has been edited by Capt Crash (edited 20 January 2001).]

[John Farley]

I don’t believe it is possible to come up with a one size fits all technique for landing with maximum safety. Pilot, aircraft, runway and weather all need to be taken into account to even establish the best plan, let alone the issues about teaching and executing the plan.

But we have to start somewhere.

Let us assume an inexperienced recreational student pilot and a light aircraft of a type that is in widespread use. We have now removed two major variables.

Such a combination should ideally not be going about their business where the runway is other than plenty long enough and the weather pretty benign. In such normal circumstances, the instructor will surely be tying to get the student to develop three skills;

A Correct visual judgement of the approach and landing that is going on

B Proper control techniques

C Flying accuracy.

Not separating out these three elements and just getting on with bashing the circuit in some generalised way and hoping it will all come good one day is not helpful for the student.

In my view these skills should be taught/honed in the order listed. A and C are at the heart of this thread.

By all means teach the inexperienced student to land 1/3 in when teaching A and B. That way you maximise the chances of leaving the student to appreciate errors and correct them without instructor intervention and also enhance solo safety.

Then when A and B are sorted (and not before) you really need to beat up on the student over C. For my money this includes a touchdown point well in (for the extra safety this provides against an engine problem on finals) BUT that does not mean you accept other than the chosen point of touchdown. If undershooting - sort it, if overshooting - go around.

Once A,B and C are sorted the available skills allow the pilot to CONVERT to a new runway type. (short, narrow, bumpy, slippery, sloping, different width/length perspective etc etc)

Such a new runway may well require the (now) available skills of C to be used to land at the threshold – or wherever is appropriate for the combination of all the factors present.

When subsequently faced with a new runway, aircraft and weather combination the inexperienced pilot can then talk to him/herself downwind about the need to consider A, B and C.

JF

[grade_3]

Capt Crash: Perhaps it is unlikely to have an engine failure due to mechanical failure on short finals, but there are other possible causes (e.g. carby icing, fuel starvation / contamination). It also comes down to the philosophy of minimising the risk. You aim a little way into the field for the same reasons you don't fly single engine over water (you don't do you ? ;) )- just in case !


JF: Thanks for the description of the method in your post. I found it very enlightening and most useful.

Cheers,


Grade 3

[Capt Crash]

Grade 3

I understand what you are saying, but I just hate leaving runway behind me. At the school I teach at we leave carby heat ON until we vacate the runway. Fuel provided at Cambridge is checked daily and as for running out of fuel....

And, yes I do fly over water all the time in a single engine aircraft.

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WHOOP WHOOP
PULL UP!!!!!!

[This message has been edited by Capt Crash (edited 21 January 2001).]

[The Growler]

If you were to aim to land anywhere else other than the tochdown zone which is generally 300 metres past the threshold on an instument runway and marked with the 'chequered' paint markings either side of the centre line, or failed to follow the glideslope information provided by approach path indicators (papis, vasis et al ) to landing on non instrument runways, then you would not get past day one of your initial conversion course with an airline. Surely it is best to tech the correct technique for each type of runway that could be used, short fields, grass strips etc require different techniques, but if you can land on the TDZ on a large runway, then you must have the skill to land just past the threshold on a short strip if required.

From experience, if you do not need to land on the threshold, then the extra fifty feet height you will have over it is an extra safety margin aginst windshear etc. It's for free as well - and I'm all for that.

BTW, regarding leaving the carb heat on until you are runway vacated - does not the carburettor heater on most piston engines bypass the airfilter and it's use decrease the volume of charge in the cylinders due to the warmer air being induced?.

I thought the proper way to use it was to turn it off prior to landing so that full power will be available for any go-around and to prevent engine damage on the ground due to f.o.d. ingestion.

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"How can we soar like eagles when we're surrounded by turkeys"




[This message has been edited by The Growler (edited 21 January 2001).]

[dragchute]

Growler,
The approach speed for a C152 is around ‘55-65 KIAS with flaps and reducing to 54 KIAS at fifty feet’ (Model 152 Information Manual). Given that a stabilized approach is achieved with a rate of descent of about 500 feet per minute, this equates to some five degrees gradient – steeper when a head wind is considered. Assuming that a threshold crossing height of fifty feet is achieved, touchdown will occur at a point 600 feet or 182 metres from the threshold. Other factors applicable to light aircraft pilots include the possibility of engine failure and approach obstacles existing on many GA runways particularly those surveyed just 150 metres from the threshold.

Most approach aids such as PAPI, T-VASIS and ILS achieve a three degree glideslope. Given that a performance type will approach at or above a Vref speed double the approach speed of the C152 but still stabilized at about 500 feet per minute the ‘aided’ glidepath will work. A three degree touch down zone will intersect the runway based on 50ft TCH precisely 1000 feet from the threshold – hence the markers.

Why would one wish to train a student in a C152 or similar to achieve a three degree glidepath when such is outside the recommendations of the POH? Airlines have the right to insist of achieving PAPI & G/S – flying schools have the right to insist upon achieving the criteria prescribed in the POH and that will probably include ignoring the PAPI or T-VASIS in day VFR operations.

Fully agree with your comments on the carburetor heat. Should be selected to cold when landing is assured. Engine life will be considerably extended if the ingestion of abrasive dust particles is avoided by filtering intake air.


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dragchute
email: [email protected]

[Code Blue]

>Fully agree with your comments on the carburetor heat. Should be selected to cold when landing is assured.

I would agree also, BUT for a student, who may not feel assured, what is best to teach them? A longish final with power at idle and no carb heat has landed some 152/172 drivers in the far fence. The accident or incident reports have those wonderful vague comments about engine failure without any mechanical findings.

I wonder if the carb heat issue isn't more safely taught after licensing.


After all a license is only a permit to learn.....

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[Squawk 8888]

Blue dude
<font face="Verdana, Arial, Helvetica" size="2">I wonder if the carb heat issue isn't more safely taught after licensing.</font>
I don't know where you fly but here in Canada knowing when & how to use carb heat is vital; we fly in the carb ice range a lot, and in extreme cold weather carb heat it can actually cause carb ice formation by heating the intake air to the icing range. There have been several engine failures caused by improper use of carb heat- the driver applied heat and the engine sputtered (indicating the presence of ice), and then panicked and closed the carb heat.

[Capt Crash]

Oh what have I started, the carby heat issue.

My employer has owned a fleet of 152s since the late 1970s and the aircraft have not suffered due to the carb heat being left on. The engine life may be reduced but they are replaced every 2000 hrs and as long as they last that long who cares. My employer is also a light aircraft maint organisation and they would let us know of any excessive FOD or ware.

When trying to teach landing we try to keep things as simple as possible, carb heat out downwind and in (using your thumb on right hand as you advance the throttle seems to work) on go-around or touch and go. If it is forgotten no big deal, the aircraft will climb at full flap with the carb heat on as long as the correct attitude is selected.

I DO understand that the way things are done are different but I don't think they are for the worse.

[chicken6]

We have two main runways, one sealed, 1100m long and a parallel grass one about 400m long. Circuits start on the seal, and eventually when teaching max perf. t/o and ldg, we move them onto the grass. It's a conversion like John Farley said, but I didn't even realise that's what we were (are) doing.

We give them the touchdown markers on the seal as their initial aim point, then they float to about the 1000' markers (C152). PAPIs on one runway and T-VASIS on the other normally show two dots high for the appropriate C152 approach. This keeps their options open, but we demand all three of John Farley's parts before sending them solo. They have to know what to do (even if it means they talk me round a circuit, how does this look? what do I have to do?), they have to be able to do it themselves and then we work on the accuracy and I mean work.

Vigilant Driver

Are the PAPIs or VASIS that you use set for your aircraft type or for a commercial length aeroplane? If the aeroplane they are set for is longer in the fuselage then a standard light trainer (C152 / PA28/38) will be landing much too far in. I agree with the "hold off" part of landing though, "Level off, power off, hold off" seems to work quite well.

grade_3

If we didn't fly single-engine over water, there would be hardly any North Island aeroplanes at Warbirds over Wanaka. We just fly from North Island shore to boat to ferry to boat to boat to South Island shore!

Oh Captain Crash, you've done it now... :rolleyes:

I fully agree with you. Except for "When trying to teach landing ..." surely this is meant to be "When teaching landing..."?


editted for speelingg
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Confident, cocky, lazy, dead.

[This message has been edited by chicken6 (edited 23 January 2001).]

[-Y-]

I just read an interesting thread covering much the same points as you have here... http://www.pprune.org/ubb/NonCGI/Forum5/HTML/000501.html in reference to carby heat, go-arounds and different approaches.

I am not totally sure about the rest of the world but the Aussie Flight Manual broadly states that for "Light Aircraft" the aircraft will fly over the threshold at a height of 50' with full flap, idle power and at the Vref (based on 1.3Vs). That part of the equation on our end of the planet is not open to interpretation...

...what is quite unclear is what happens in the "period of indecision" between 50 feet and touchdown! This is left to the individual operator. Most would argue that you would hold Vref to the flare and ideally touch down at the nominated touchdown speed. This becomes awkward when it's the same speed that you have maintained til 50'agl. Regardless, it should theoretically be done. TKOF and landing distances are calculated using this method so you're not going to run out of runway if you did your math right.


Having said that, I think it's in every instructors best interest to "share" the aircraft's operating envelope with a student. Even though the published performance charts are based on achieving 50 feet above the threshold under the above discussed conditions - it still makes sense to teach real short field performance. Aim for the grass to touch down on the first inch of runway kinda thing...and find a local grass runway if you can - makes it more fun and helps make it "real".

Each company should have it's own approach procedures for both the instructional training syllabus and 'real life' commercial operations. Read your Operations Manual as your bible. If you have ideas, comments or suggestions tell your Chief Pilot who can possibly action the change if it's in the companies best interest. dragchuteillustrated this. I don't think that a 1.1 Vs is in the POH but in the light of operational experience if you can prove that it works you can write it into your SOPs or Ops Manual and then it does become legally binding. Your company then accepts responsibility or becomes 'liable' for your operating procedures...very different to becoming responsible for your flying mind you.

Capt Crash. If leaving carby heat ON until after landing is what your company does - good luck to you! We couldn't get away with that in the heat at Sydney (or anywhere else in OZ) when you REQUIRE full power out of the engine at times. Full power is NOT possible with carby heat on. I would suggest you re-think your company’s approach here. I do think this is a terrible idea for all the reasons discussed in other posts.

[Noggin]

I thought the original question was where do we aim to land on the runway, not HOW!

[Squawk 8888]

Y, I think Crash meant carb heat on until touchdown, which is SOP at all the schools I know in Canada. During the rollout we take carb heat off then raise the flaps. In a Go-around, our procedure is nose up, then full throttle, then carb heat off, then flaps 20.

[Code Blue]

Squawk:

I fly around NF and Lab, most of the time with carb heat on and a little extra leaning to compensate. Of late with temps below -15 regularly I find carb heat produces very little effect one way or the other, I suppose because the humidity is so low. I use it only on descents and touchdown & push it in on roll out. I obsess about it in summer :)


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[This message has been edited by Code Blue (edited 24 January 2001).]

[dragchute]

Y

…”period of indecision” between 50 feet and touchdown… Check our Part 4 of the POH specific to aircraft type.

For instance the Cessna 152 manual suggests “…make an approach at 54 KIAS with 30 deg. flaps using enough power to control the glide path. After all approach obstacles are cleared, progressively reduce power and maintain 54 KIAS by lowering the nose of the airplane. Touchdown should be made with power-off and on the main wheels first…slightly higher approach speeds should be used under turbulent air conditions…” CASA Flight Manual nominates 54 KIAS (1.3 Vs) as approach speed.

I find that once power is reduced to idle at fifty feet and speed pinned at the prescribed figure, continued monitoring of the ASI is unnecessary. Your student should scan the touch-down zone and the upwind end of the runway. During the flare, speed will reduce as induced drag increases. Ground effect will compensate.

My comments pertaining to 1.1 Vs were included to simply demonstrate the margin of safety built-in with 1.3 Vs. Our operational reasons for using such figures revolved around SAR and similar issues and I would NOT advocate such techniques unless circumstances left little or no alternative. We trained regularly to fly accurately at such reduced speed – and the tail-wheel configuration and spring-steel legs ensured adequate propeller clearance and shock absorption resulting from such a steep approach.


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dragchute
email: [email protected]

[Turbine]

Squawk 8888, if that's your SOP then great, however I do have to disagree with the way your copmany operates.

<font face="Verdana, Arial, Helvetica" size="2">During the rollout we take carb heat off then raise the flaps</font>

Most would argue that touching anything at all on the runway is a bad idea. Our company policy prohibits the retraction of flap until clear of the runway. Even after exiting the runway a visual identification is made by the Captain - followed by identification and verification by the FO. Rolling down the runway is not the time to be doing this. If single pilot and in the heat of the moment you can quite easily inadvertantly retract the gear. What you are doing by adhering to your company SOPs is maybe doubling your chances of retracting the gear by retacting flap and turning carby heat off.

Retracting flap on the roll has it's time and place but certainly not under normal operating conditions.

<font face="Verdana, Arial, Helvetica" size="2">In a Go-around, our procedure is nose up, then full throttle, then carb heat off, then flaps 20.</font>

First, applying the nose up to the climb attitude in most training aircraft (especially if at low or idle power) can possibly result in a stall. I assume you got your procedure a bit "backwards" and power is applied before pitching the nose up into your positive climb attitude?

Second, you should really apply carby heat to the off position prior to applying full power. Full power (when carby heat is on) may possibly result in detonation (i.e. very high CHTs and low approach speeds).

Correct use of carby heat

The correct use of carby heat is defined differently in different climates, condtions and countries. Where you may not use carby heat ever in Central Australia, for example, you may find yourself using it often on the South Coast of OZ.

Use Carby heat when either:

a)The Aircraft's Flight Manual Dictates its use at a particular power setting or particular climatic conditions;
b)The Conditions are conducive and you suspect that Carby Ice will form - this is open to interpretation from pilot to pilot. Most people generally use RH 50% or greater and a temp range of -10 degrees to +25 degrees celcius. There is an excellent chart produced from CASA that, based on current conditions, assess your carby ice risk. I'll try and locate it soon...
c)You have ice and want to remove it.

Our own Operations Manual requires carby heat to the OFF position by 300'agl if it was applied so maximum power is available in a go-around. Keep in mind though that although you want maximum power available to you in the missed approach - that does not mean that carby ice will not form with full power set. You must stil keep a good lookout out for the symptoms of the formation of ice.

Minimising the use of Carby heat will undoubtedly increase the life of your engine. Remember that's it's hot unfiltered air that's making its way into the cylinders - not a good thing!

Bottom line. Read your Copmany SOPs, Flight Manual or Pilot's Operating Handbook. If it has been written up correctly then there is a relevant section explaining your company procedure on the above matter.

Touchdown Point

As -Y- correctly pointed out, the aircraft shoud fly over the threshold at Vref (based on weight), with full flap and at idle power. If flying to a PAPI or T-Vasis that should have you aiming for the 1000 foot markers (which equates to 3 degrees). I think the US use a slightly shallower ILS approach (maybe 2.7 degrees?) Unsure.

It's actually a really good argument the whole touchdown point thing. I worked at a company once that encouraged a high approach that would permit a landing from anywhere in the circuit - including a base or final. Other schools encouraged the Airline approach utilising the PAPI or T-vasis for guidance. Other taught reference points on the nose (i.e. threshold on the nose to touchdown on the numbers). It's all up to the operator. Our copmany policy has the MetroIII and other larger turbines fly at 3 degrees but we teach abinitio students in Cherokees to come in at closer to 4 degrees.

Each to their own I say. If it's in your SOPs, if you can justify it and you always thrive to improve your standards and consistantly account for the way you do things then you're doing it right!

[JamesG]

John Farley

With your permission, I would like to cut across your mail to the Private Flying forum as I think the clear approach that you outline would be very good as a self checklist for PPLs progressing to more challenging fields.

[bookworm]

Capt Crash

As JF eloquently points out, there's a major difference between teaching your students to fly accurately and teaching them to land at the end of the runway.

Landing short on 05 at Cambridge is a fairly high-risk venture. You have a choice between Sainsbury's car park and the sewage works. If you land very short, you'll take out my house! So I have a personal interest. :)

Given that there's some 1670m from the threshold, and that Cessna 152s taking more than 1200 m to land are even rarer than engine failures on final, wouldn't you agree that it's sensible to pick an aiming point some way in to the runway (taxiway D always seems sensible to me)?

[Squawk 8888]

Turbine the procedure I described was for a C172, I agree about the flaps/gear problem with other types (saw an Aztec crew raise gear on R/W during a touch-and-go). Raising flaps during the rollout is useful primarily on short runways, by transferring weight from wing to wheel thus improving braking action (which is mentioned in the Flight Training Manual- Aeroplane in Canada). I should have been a bit more specific about the sequence we use in the go-around- we raise the nose to a level pitch attitude (similar to the flare) while simultaneously applying full power, i.e. we've got max RPM just as the nose is passing the horizon. Not sure exactly why, but I would guess that being nose-down at full throttle only a couple of hundred feet up would be considered by some to be a tad riskier than a stall. We do our approaches at 60-70 KIAS, and with a clean stall speed of 47 one would have to be pretty slow on the controls to stop flying. Once we have full power we adjust the pitch to get our climb speed.

Code Blue my instructors always warned me about carb heat in extreme cold- if the OAT is below the carb ice range then carb heat could warm the air up to the point where carb ice can form. I was taught to bring the carb heat on before bringing power below the green arc as a precaution, because if it's needed later the engine will be too cold for it to be effective.

[Code Blue]

&gt;if the OAT is below the carb ice range then carb heat could warm the air up to the point where carb ice can form. &lt;

I seem to recall a mention of this but it was then almost dismissed with comments about very low humidity with the cold temps.

&gt;I was taught to bring the carb heat on before bringing power below the green arc as a precaution, because if it's needed later the engine will be too cold for it to be effective&lt;

Moi aussi.
Perhaps some of the comments here relate to vastly different climates and humidities.

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[Squawk 8888]

I'm sure they do, Bluedude. Humidity is definitely the biggest factor in carb ice- I remember those graphs that show carb ice danger at temps of 20c when the humidity is high enough; basically the more humid the air, the further from freezing (above or below) carb ice can happen. I'd wager that at this moment the risk of carb ice is higher in Florida than it is in Toronto. If any of the scientifically inclined out there wish to sponsor me on an expedition to test the hypothesis I suppose I could make the effort :) All in the name of research, of course ;)

[John Farley]

James

Please be my guest.

Regards

John

[kala87]

Going back to the discussion of runway touchdown/aiming points, surely the "one technique fits all runways" approach must be too simplistic, because there is a wide variation in runway lengths and associated approach paths/obstacles out there. Each approach to each runway needs consideration on its own merits. This is something that every pilot surely learns as he/she progresses after gaining a licence, assuming that the pilot does more than just fly around their local strip.

For example, at the grass strip where I did much of my PPL training, the longest runway is 1800 feet. Landing on one end, with a significant downslope, you need to fly the final approach close to Vref (say 60 kt in a PA-28, 55 kt in a C152, plus any gust correction) and touch down close in to the threshold. Landing from the other direction is quite different. The touchdown point is one-third of the distance down the runway. Reason: If you try to touchdown closer to the threshold, you might end up in a stand of big oak trees conveniently located under short finals!
The technique in this situation is to use full flap, closely controlled airspeed, and lots of throttle control to carefully control the glidepath. Oh, and I forgot to mention the deep valley just before the trees, where you usually get a nice bit of sink at the wrong moment. Not to mention the "interesting" gusty winds that invariably blow in from the Atlantic most days.

Just cruising down finals with the engine idling isn't a realistic option here!

PAPI's and VASI's?? Forget it! No such high-tech gizmos!