What that man said:ok:

No but clearly they have to hand feed it to you.

What I'm saying is that you manage the aircraft energy with the thrust. And that is applicable in all phases of flight. You don't have to invent a new rule of thumb for every different phase of flight.
If the energy state (the forces that act on the aircraft) is not in equilibrium you will see either speed or vertical speed changes. Which in effect are pitch changes.

but when your buddy Bloggs starts to contest that a flightpath is the resultant of vertical and horizontal movement then something is seriously wrong with basic understanding of physics. and in that case those type of people meed to be handfed information!

The difference is that when I feel an updraft, seat of the pants and all. I immediately reduce thrust in order to balance the energy and at the same time I adjust the pitch required.
You lower the nose and then wait for the speed change that WILL follow, only then you reduce the thrust thinking that you are controlling the speed, whereas you are simply reducing the energy the aircraft has in order to reach your desired stable flightpath. Its the same thing.

See speed doesn't change on its own, it changes due to an energy change, this change is absorbed into vertical speed or speed depending on the pitch.

What are we inventing exactly??
Apart from CLB or OPEN DESC what modes aren't THRUST for SPEED?

When I feel an updraft I immediately ease forward on the pitch to maintain the GS then and only then do I adjust the thrust to maintain the speed. The thrust may not even need to be adjusted for minor changes....

When I feel a sink I immediately ease back on the pitch to correct the ROD, most times considering the inertia of the heavy Jet I still won't need to increase the thrust BUT I'm ready to just in case.

You cannot effectively use pitch to vary the IAS at it takes too long to effect an outcome and you'd need to adjust the thrust anyway. Not to mention they don't want you push forward at low level!!

There in lies the crux of the whole matter, THRUST CONTROLS THE SPEED MUCH MORE EFFECTIVELY IN JET A/C.

Gee, I thought the last 6 pages has been about using power to control the glidepath and elevator/pitch to control the speed. Now you are actually pitching (down in your example) AT THE SAME TIME as pulling the power off. Glad to see you're coming around...
:D

Energy? May the energy force be with you, 737jock. :)

well bloggs I refer you to my first post on the matter post 47

clearly if you could read... You would see that I actually said the pitch will change.
Cause the pitch controls the speed and the vertical speed, which controls the path. But you don't even understand what a flightpath is.
So instead of thinking that I'm coming around how about you study a bit. Cause nothing what I said is contradictory.
The statement that thrust controls speed is as correct or incorrect as the statement that thrust controls vertical speed. It only does so because we are unable to detect energy requirement changes fast enough.

You have a lot of studying to do Bloggs, physics, aerodynamics, but more importantly reading.

I would start with learning how to read and actually understand. Its probably why you are having so much trouble with physics and aerodynamics.

I thought...power controlled...which one again? I need more energy. My brain's hurting! :}

Weak arguments and trying to ridiculize your opponent. Typical for people who lack intellect. What's next call me a nerd and show some muscle?

Bizjet - in general I'd agree with you but you but I doubted the accuracy of your comment about the wing loading of 1960 fighters vs. modern airliners. Turns out you were correct. Learned something new today.

Fighter from that era were in the 70-80 lbs/sqft range. Modern airliners are in the 120-140 lbs/sqft range. The only 'F' series a/c that approach 120-130 lbs/sqft is the F-111.

Nicely done.

Comparison of Aircraft Wing Loadings - Military and General Aviation - CombatACE

Capn Bloggs - you need more energy? What's your potential vs kinetic energy state? What's your energy state vs. your desired flight path? Is your thrust in a fixed position or is it variable(ie not at full power).

Like I said, I'm glad we finally solved this issue.

and so on... :D :D :D

All those statements are based on your posts. Or in reply to nitpickers post who also has the tendency to ridiculize. You (Bloggs) misread and misinterpret.
You demonstrate a lack of knowledge in physics and aerodynamics. And when confronted with verifiable information you ignore it instead of trying to understand it.

It's not ridiculizing to point out simple facts.

But keep working on those emoticons. Another sad example of not being able to have a proper debate.

:eek:

John Tullamarine

Time to lock this thread buddy, waste of time now.

These Physics professors and Aerodynamic class room experts can fly their chalk board the way they wish and there can be no doubt their theories are correct with regards to momentum path vectors inertia etc etc.

Me? I'm sticking to the way Airbus want me to. Keeping it simple easy to use and safe for real world operations. KISS method.

LOCK IT IN EDDIE. ( John knows what I mean )

Nitpicker330, I think most of us had this behind us by our private pilots license.

I agree, this thread needs to be closed.

The airplane does not care what you think controls what. The reality is: the throttle controls ENGINE POWER (Thrust) and the yoke / stick controls PITCH (or indirectly, AOA). The combination produces performance. You choose which controls which as a TECHNIQUE based on what you are trying to get the airplane to do. Obviously by the endlessness of these arguments, they both work. Regarding jets, if you observe how modern auto flight systems work (A330 and B717) you will see 2 main ways they are programmed to handle speed. First is "speed-on-pitch", where power is fixed at a set value by the autothrust / auto throttle (climb, TOGA, flight idle) and pitch is varied to maintain selected speeds. Second is "speed on thrust", where flight path (vertical rate or angle, a glideslope, VNAV path, or level flight) is maintained by pitch and the power is varied by the autothrust to maintain speed.

Notice that in "speed on thrust" mode both adjustments always occur; if you are in (Airbus speak) ALT CRZ and hit a mountain wave updraft, the autopilot will pitch down slightly to hold altitude, and reduce thrust to hold something close to cruise mach. This is, strictly speaking, a technique. It makes the most sense to think in this manner so the designers programmed the airplane to think this way. It could be argued that the airplane pitches up to maintain speed, and concurrently reduces power to prevent a climb. Some people fly this way (or at least that is what they choose to think, rather than visualizing the "speed on thrust" scenario). Imaging you were hand flying a 172 in a similar, smooth wave updraft and wanted to hold altitude and speed (good luck). You would probably follow an intuitive technique similar to one the Airbus uses to fly itself. However, you COULD choose to think differently and be a strict "elevator controls speed" guy, jockeying the throttle back to reduce excess thrust and therefore counter the updraft, while gingerly pitching up in opposition to the thrust reduction to get the speed back. For light planes that do not have much excess power, this is a good way to think; it will help you make the right move when you suddenly find yourself closer to a stall than you thought you were. Come to think of it in light of AF447 it has a place in jet flying, too. The point is in the end it doesn't matter how you think about it, you will intuitively move both at the same time, as needed to get the job done. Yoke = elevator / pitch, throttle = engine power / thrust. Speed is part of the resulting performance.

This argument is ages-old as we all know. Bob Buck in his many books advocated the "elevator for airspeed" theory (and with his varied experience I would listen to him); Jim Webb in "Fly The Wing" (the American equivalent to "Handling the Big Jets") advocates the opposite. I would listen to him, too. And really, don't we tend to use both? On the glideslope a momentary above-path deviation can be quickly countered by a little pitch down; we pull back the power to keep the speed from building. But if we keep trending high over the long term, a very slight reduction in approach power setting is probably what is going to do the trick. We then subtly adjust pitch with power to hold our speed. It's all just in how we think about it. So we use the most appropriate technique for our airplane, situation, maneuver, and in some cases just personal preference. In the Boeings and Airbii (particularly the latter, as the fly by wire system decides your technique for you a great deal of the time) with the autothrust on, we fly whatever technique we have the system programmed for. And if we disengage the autoflight, autothrottles, and flight directors (talking 717 here) we fly just as in any other plane.

Recall that in a STABLE idle power descent, we can switch between VS and OPN DES / Idle Clamp all day long and the flight path, attitude, and power setting will not change if nothing disturbs the airplane's "groove".

Everybody here needs to take a deep breath, drink a beer, and focus less on how we THINK about flying and just go out and enjoy DOING it. Myself included. Ready 3-2-1... pf-FSSSS! That is a Peroni opening. I believe I will let the airplane do all the thinking this weekend and just enjoy the flying part.

I have followed this thread for many days now and have enjoyed every part of it. I del I have to be a part of it before it goes inactive.

One of the easiest examples to understand what controls path, is while we maintain steady descend and we realize we are going below path.
At this point, further pitch up without thrust addition might produce a greater rate of descent and cause the airplane to sink more below the desired glide path.

This makes clear that path is controlled by thrust.

I see that old jocks have withdrawn their interest in the thread, and the ones seemingly "celebrating" their win are the ones that (to me) are advocating the wrong way of teaching things.
i have no Airbus experience, but I have a lot of jet experience. Light, heavy, military, supersonic, all kinds of.

The physics behind the flight and handling of jets will always be the same. Engineers come up with new solutions to make dumber pilots feel better, but the physics will always be the same.

An the truth is that pitch controls the airspeed. i will have to agree and support the minority in this thread. It is difficult to do so, but it is not unusual that the minority is right, and that most people do it the wrong way.
Engineers will come up with their best way to make them feel like the best pilots, but the credit must go the engineers.

Some replies about "region of reverse command" etc, are utter bollocks if I may say. The person that posted this is entirely clueless of what he is referring to. I would say that 50% of the replies are irrelevant and -simply- wrong.

The simple truth is that modern aircraft can fly any way you want them to, forgiving many mistakes. BUT, a good aviator is the one that does not rely on a good engineer (only), and knows the principles of flight and how to control his machine without any automation.

Some posts use all the terminology they can fit in a sentence. Just to cover their lack of knowledge and understanding of the basics. Remember, in science, it is the simplest theories that take the longest to really understand.
Physics is one of them and principles of flight is the best example.

I am old school too, and I will have to say that the old books have served me well along with many others, unlike the sim games and the youtube videos.

So I will encourage the new ones in this trade to study these old textbooks and listen to the minority in this thread. Keep it simple, it will never change. Maybe a brilliant engineer will make it seem like it changed, but it will be the computer correcting and anticipating your incorrect input instead.

The Naval Aviator's book is a brilliant one to read and refer to throughout one's career. It is too scientific for most, but it is very explanatory and covers all aspects of flight. Pity that most people think it is obsolete nowadays.
You should try reading it.

Fly safe and learn as you go.

St martin: I would like to see how you manage to stay on the glideslope in an approach with fluctuating speed (say +/- 5 or 10kts). You will be all over the place if you chase the speed with pitch mate. The larger the aircraft the more obvious this becomes.

The simple fact is thrust overcomes drag which causes an acceleration and therefore a speed change. It is because of this speed change that the RoD eventually changes.

Well this is where the airframe is on a swept wing aircraft on landing...On older jets this was a very sensitive area and besides the "fighters", no one would get there. Todays technology ( Airbus, Boeing, and the first of all Dassault) managed to make these aircraft flyable by the "average" pilot in this phase of flight. The flare is (was) the last part of the flying devoted to pilot authority; not quite nowadays. Once the aircraft is passing the 50ft mark RA it triggers the flare sequence ( except at LCY with the 318 where it does so at 80ft); from there on you can dream about controlling the things, but the plane will land and flare by itself ( if you were at the proper speed, in the bracket that is). You can take the stick all the way forward, 6 seconds after main wheel contact , the derotation sequence engages, the engine idling sequence changes from landing idle to reverse idle, and if the reverses are not selected within 6 seconds of NW touchdown, they go on ground idle. The laws are changing constantly during this phase of flight..

Get on a sim of a falcon 10, select full flaps on a 3° ils, let the speed decay to below 1.2 Vs, and tell us what is controlling your speed/ ROD.... Then step on a F7X sim and do the same... Alternatively, choose a 727 and a A320 if you do not like 'small' planes... then do it on a 172 with jet.. aka Citation 500..
Start the exercise at 200 ft, and let's post which configuration made it to the runway....:cool:

My dear friend, your comment is quite childish.

Why chase the speed?
+/- 5-10 while on glideslope with unstable weather conditions, you should keep the thrust unchanged and it will come back to where it is supposed to right after the gust.
The larger the aircraft. the more the inertia it carries.

You never chase the speed in a large airliner.

I suggest you read my post again, as you are replying to something irrelevant.
Realizing a trend to go below path while steady on the speed, you should add some thrust to bring her up to path again.

Thrust can overcome drag and cause acceleration of the mass, I agree. But you choose the vector. Your airspeed does not necessarily change if you start climbing. Right?

:ugh:

Pff-FSSSSSSSS!!!!*

That's an Anchor Steam Lager now, San Francisco's greatest gift to the aviation community. Come on boys, cut the semantic nonsense and start drinking and relaxing. It's a damn airplane, not a moon launch. We're all right and we're all wrong, depending on who you ask. Don't get so worked up about it.

Pfff-FSSSSSSSSS!!*

This Bud's for you!:8

Ha ha ha ha ha ha

So funny I laughed my a** off.

2 hours ago I landed in HK on 07L with tower reported surface wind about 180/18 gusting 20, Mechanical turbulence off Lantau, Windshear forecast AND reported.

Quite a sporting approach, ended up with about -8 ( back to VLS ) to +15 FROM about 100' down to 50'. Kept under control and guess what:--

I used THRUST to manage the IAS. Only after giving it a big boot full for a few seconds did the IAS return to VAPP at 80'.

I'd like to have seen you control that with Pitch only!!!!!!!

Yes a Jet has a lot of inertia but I can tell you that 100' ain't the place to hope the speed comes back by itself, so those saying it will stabilize all by itself don't know what they are talking about.
God you'd be dead after hitting the sea wall whilst waiting for IAS to return using only Pitch...

Yes for small changes you could control IAS with Pitch if you felt so inclined but not today boys and girls...

So why did your speed change in the first place nitpicker?

I give up. Thrust for Glide path, Rudder for Roll, and Ailerons for Yaw

Well gee whizz Jock why do you think?????

Maybe the Wind velocity and direction changing around after interference from the hills and the Heaco Hangar might be a reason. They call it mechanical turbulence my friend, they even talk about it in the Jepps for HK 07L if you'd like to look.

What's your point? Are you going to mention energy levels, path management and inertia again?

Quite a few contradictions there I would say. Maybe you want to review the values?

I thought you were at +15 from 100' to 50', why did you increase thrust?

No I'm waiting for your explanation why the speed changed. So the wind changed, And you encountered up And downdrafts.

What happened aerodynamically that made your speed change?

For gods sake give it up with the aerodynamic mumbo jumbo.

I flew the dam Plane Maverick and at 100' I ain't got time to think about all the aerodynamic reasons for the flight path fluctuations.

When the IAS is heading south at around 100' with a rather long trend vector I'm not sitting on my hands hoping "inertia" will save my ass. Neither would you.

And yes the first post I made describing the events were correct, speed loss corrected by me followed later by a speed gain. ( which was not caused by me leaving the thrust on too long )

Ok I edited the post to include the word FROM to highlight the area from around 100' to 50'

The values are corrrect?

So Lets assume your Vapp = VLS because you are flying manual thrust approach.

You landed on runway 07 with 180/18 maximum 20. (What value is needed to report a gust in the towerwind?) Means you had a 7 kts tailwind.
What was the wind on the approach?

The way I understand your post the way its written:
You ended up with VLS -8 somewhere above 100ft. The speed then increased to VLS+15 from 100 to 50 ft.
You added thrust at 80ft?

Did you mean that:
At 100ft you lost 8kts of airspeed resulting in VLS -8
Then at 80 ft you added a boot full of thrust resulting in the speed increasing passing VLS to VLS + 15?
After which you reduced thrust to settle at VLS?

No mate. Tower reported wind was from memory 180 18 gusting to about 23?
Nearly all crosswind and only up to 5kts tailwind, no report of shear from the 748 ahead.

VLS was 134, VAPP 142 as per company policy for gusty conditions and experience on type. I Used managed speed with manual thrust as also recommended by Airbus in gusty conditions.

At around 100' or so the speed dropped quickly to around VLS, so it dropped by about 10 kts from what we had. I corrected quickly and the speed settled back to about VAPP.

Then about 50' the speed shot up to about VAPP +15 or so just as we entered the flare.

We landed safely used full reverse and vacated A9.

Ok?

Isn't that what I said the first time?

Well nitpicker you landed on runway 07L. which is approximately 070 degrees.

Means wind is coming at you at 110 degrees, thus a tailwind component.

At 180/18 that is 7kts tailwind and 17 kts crosswind, at 180/23 its 8kts tail and 22 kts cross.
So yes its mostly cross, but if your tailwind limit is 10kts like on the minibus you were very close to it.

Remember at only 30 degrees off the side you already have half the wind component.

And no its not what you said first time. Which is why I asked clarification. Won't hold that against you though, I imagine you are tired after a long flight.

I hand-flew an ILS yesterday (with the ATS engaged :eek:); the conditions weren't nice; bouncing around all over the place. I can tell you one thing; I like nitpicker wasn't waiting for the thrust to fix the glideslope: I poled the aeroplane so it stayed put on the glideslope and ATS just controlled the speed for me (as I would have done had it been disengaged).

For the life of me, I cannot understand how 737jock and his mates can think they're best off picking up slope excursions with power.

No it doesn't, it shows that the pilot involved was either stupid or taught by a twit. If you are below slope and going lower at constant speed, of course it's going to slow down/go down if you pitch up to get back without adding power! Attitude + POWER = performance... But fix the slope first and then the speed (if indeed anything needs to be done about the speed at all).

Aww shicks, that's nice. Picker, lift yer game, lad! Long flight or not, the power-for-slope lawyers won't stand for anything less than the whole truth the first time...

Hey Bloggs is back what a coincidence....:E

Bloggs what I actually said is that both explanations are incorrect or correct, whatever you want to call it.
The problem is actually that you don't want to accept that thrust for speed is only a simplification.
And that you refuse to believe that thrust for path is a similar simplification that holds just as much merit.

Thrust manages energy, and the pitch manages airspeed and vertical speed.

Yes, mate, I just got back from flying. I got a bit high on final. I said "no you don't", stuffed the nose down, got back on slope and didn't even touch the power (well, ATS didn't move). If I had pulled the power back (override ATS) I would have been there for too long waiting for the machine to first slow down then second drop down onto the slope. I have better things to do.

When was the last time you touched an aeroplane?

8 times in the last 4 days buddy on the minibus, all without autothrust.

Nobody was contesting how the autothrust system is designed. Flying with autothrust is not manual flying. Just saying....

Magnetic runway direction for 07L in VHHH is 073
Magnetic tower wind was 180 18 G 23

Giving a xwind component of up to 22 kts and a tailwaind component of up to 5.3 kts ( oh and Max Tailwind for the A330 is 15kts )

I think your pencil is too thick.:D

Me? I used 2 different Apps to check it in the hotel!!

Yes I am a bit tired.

Friend that landed behind me in a 777 did an Autoland!! Slack bugga, I couldn't have even if I wanted to in the blunder bus!!

I used an app as well (airports). I used 070 as I don't know the exact magnetic course.

But if you want to be exact:

5.26 at 18 kts And up to 6.72 at 23 kts

180-73= 107-90 = 17

Sin 17 x 18 (or 23)= 5.26 And 6.72

Good that its 15kts Max tailwind! Wish my boss had paid the money to change some letters in the FCOM of the minibus. Would prevent some of the nasty circlings we sometimes encounter.

Either way tailwind component was not my primary concern today!!

Sin this, tan that.......I either use the graph in the QRH which is crap or I use an App designed to make my life a lot easier on the spot.

Don't do tan. Use cos for the xwind.

I'm glad to see you appreciate the science that goed on behind all these things.

I do appreciate the theory I learned 25 years ago but at the end of the day I'm just another dumb Pilot that flies the Aircraft the way I'm told to. I don't have the luxury of questioning science while I operate my Airlines 100 million dollar Jet. It's their train set and I'll do it the way I'm told. The Airline in turn does it the way Airbus tell them to do it to minimize litigation against themselves.

It's all about butt saving at the end of the day.!!

Like I said KISS method works for me

Hmmm for me its all about doing a job I enjoy.

If I had to save my butt everyday I come to work, I would do something different.

I think about these things outside the flightdeck, I believe that improving my understanding makes me a better pilot inside the flightdeck especially when confronted with non-normal circumstances that haven't been catered for by the litigation experts.

Obtaining a deeper understanding doesn't make you a danger to safety!

But if you like to see yourself as a dumb pilot, go ahead. I find that description wholly unsatisfactory.