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quid
29th Jul 2001, 09:38
Flying “on the step”. It’s been written about, talked about, debated over the years and there are still two opinions.

Some of my co-workers and I disagree, so I’d like your opinions. Some factual or written data to back it up would be even better.

Just to make the question clear: You are flying a swept wing transport jet. When you get to cruise altitude, you let the speed build up to .02 or so above the LRC cruise Mach to get it “on the step”. Now you can enjoy a greater TAS than LRC for the same cruise power setting (fuel flow) by virtue of getting it “on the step”.

Is there a “step”? Fact or “Old wives’ tale”?

;)

411A
29th Jul 2001, 10:44
Could do as you suggest, however assuming power settings and weight are correct, the speed will soon decrease to LRC or the desired mach number acording to the cruise performance data chart. True in B707 & L1011, suspect the same in other types.

atomic
29th Jul 2001, 13:35
"Folks, we'll be landing in Alabama soon, please set your watches back 6 years...."

My old TV set and I can prove that sound is actually faster than light: When I turn it on, I can hear the sound before I see the picture!!!

There was an interesting show about this (faster than light speed and time travel, fascinating stuff :)) on PBS last night.
Check your local listings......

Mr moto
29th Jul 2001, 15:46
The misleading term 'on the step' is just a way of saying that you have reached the max level cruise speed for the power setting.

If you set the cruise power setting on reaching the cruise altitude the aircraft WILL accelerate to this speed.
You can reach this speed quicker by maintaing the climb power and accelerating to a higher speed and decelerating.

When all the forces are balanced out the result will be the same, all things being equal.

There's no mystery.

Nick Lappos
29th Jul 2001, 20:43
Some thoughts from an aero engineer, but admitted helo driver:
The term "on the step" originated with flying boats, I believe. The hull could plow along as a displacement hull with much wave drag, and only make about 15 to 20 knots with max power. As a wave or some forward stick made the hull climb up into a planing mode, (on the forward step of the notched hull) a surge of acceleration is felt as the same power produced much more speed. Today's planing hull pleasure boats illustrate this as well.

In flight, the very draggy flying boats are said to have had almost no cruise speed increase above climb speed when at continuous power (the joke was that the PBY climbed, cruised and descended at 90 mph.) With the aircraft stuck at the bucket (bottom of the drag curve), a gentle dive to the forward edge of the bucket could increase speed by 5 to 10 miles per hour with no measurable power change.

Such conditions will not exist for a modern airliner, with a vast speed range beyond the bucket. In the cruise power range, the power required goes up by the third power of the speed, so even a few knots change will produce a measurable power need (or a descent).

pigboat
30th Jul 2001, 08:46
Nick, that's the best explanation of the phenomenon I've ever seen. That description of the PBY was pretty accurate. For a given cruise power setting, say 550hp, depending on cruise weight, you could indeed squeeze extra mph out of the thing by climbing a couple hundred feet past the cruise altitude then begin a gentle descent to cruise. I did familiarization on the C-46 our company owned, before it was sold, and that technique worked for that aircraft as well.
The single Otter was another aircraft that needed a certain touch. Loaded, this aircraft was very tail heavy, particularly on floats. The trick was to add a few degrees of flap. This seemed to raise the tail a little, and the aircraft flew better. Added bonus was a reduction in CHT's.
Your first paragraph, about water operation, is also bang on. You could sit there all day using great whacks of power, going nowhere fast, if you weren't 'on the step'. To get 'on the step', hold the stick full aft, add take-off power and wait until the nose rises as far as it will go. Ease the stick forward and you will feel the aircraft begin to accellerate. You then allow the aircraft to reach flying speed, and fly off the water in that attitude. If you want to establish a 'step taxi' attitude, once the aircraft is planing, reduce power to a setting that'll maintain the planing speed. Then ease the stick forward until you feel the aircraft begin to decellerate slightly. Be very careful doing this, as the aircraft becomes directionally unstable.Ease the stick backward again until you feel the aircraft accellerate and it regains the lost speed. Note the attitude where the aircraft planes most easily. Voila, this is the step attitude for that particular configuration.

LeadSled
30th Jul 2001, 09:14
Folks,
I think you need to consider jets in a different way to the PBY.
In fact, go back to some of the old standard text books to see the explanation of why a straight wing piston engine aircraft has two cruise speed for a given HP setting, that is what the PBY is doing.
Have a look at a typical L/D curve for a jet, it is much "flatter", and yet we found an equivalent to the older aircraft, from practical experience.
Some years were to pass before a theoretical explanation for what we knew in practice happened, there wasd a "step".
What seems to happen is that the boundary layer adhesion and hence a large lump of the drag, differs at a given Mach No., depending on whether you accelerated to or decelerated to that cruising Mach.No.
I found the "step that wasn't a step" very evident on B707 ( both -300 & 320) and B747 SP/200/300, but not so on B767-200/300 of B747-400. Not a ETP standard of analysis, but there you go.

cosmo kramer
30th Jul 2001, 15:35
"Some factual or written data to back it up would be even better."

I don't know how factual this is, but it's written :D

Aviation Myths (http://www.avweb.com/articles/myths/)

pigboat
31st Jul 2001, 05:51
Leadsled, you are of course correct not to compare a modern aircraft with a PBY. The techniques I described work for the three aircraft I named. I'm certainly not claiming that they would apply to any other. I obviously didn't make that clear. :o

cosmo, here's something that was written.

We pass through ten thousand feet and for a moment steal an additional hundred feet so we can descend back through it. In the doing the ship can be set flying in a slightly nose-down position. Thus, "on the step" we will add better than ten knots to our air speed and also satisfy our sensual appreciation of flight. A mushing airplane, regardless of its speed, becomes a miserable contraption to any dedicated pilot. He absorbs this unhappiness through the seat of his pants. There is no reason to believe this will ever change regardless of aircraft design. A good pilot becomes morose and irritable in spite of what the most modern instruments proclaim unless his ship is "on the step." He will work endlessly to achieve that delicate angle and for this once and only once will prove the instruments wrong and the hair tips of his sensory powers more honest. When the instruments finally admit additional speed, then the pilot is doubly content, for he has proof that the instruments are not his absolute master and he is not as yet altogether a mechanical man. :D

[ 31 July 2001: Message edited by: pigboat ]

GlueBall
31st Jul 2001, 07:03
When you're "off the Step" you can feel it because the deck angle is too high, having to exert greater effort working your way "uphill" upon returning from the forward galley.

When the FMS calls for M.838 LRC, I set TM @
M.844 because I don't want to get close to falling off the "LRC step." Besides, the airplane just doesn't feel right below M.84.

:cool:

Vmu
31st Jul 2001, 16:34
The one thing that I hate the most in this world, is when my captain starts talking about "the step". In a normal airliner there is no step, as long as you fly above the minimum drag speed. Had there been a step;
1. Manufacturers would have made us aware of it and,
2. We would have had speed instability in that airspeed region.

I find it embarrassing when some of my colleagues believe there is "a step" around cruise speed. It reveals a complete lack of understanding of the most basic principles that govern the flying abilities of our offices.

[ 31 July 2001: Message edited by: Vmu ]

Capt Snooze
31st Jul 2001, 21:30
Ahhhhh......

pigboat

Fate is the Hunter
Ernest K Gann

Chapter 17

:D :D :D :D

Still the Bible...............

:cool: :cool:


Snooze

quid
1st Aug 2001, 01:42
Let's see.....Ernest K. Gann....Fate is the Hunter...

That's a book of fiction, right?????

;)

LeadSled
1st Aug 2001, 10:40
Re.Gann, What a writer, he was almost as good a writer as he was a pilot, and Fate is the Hunter was far from fiction.He most certainly had a considerable experience of the performance of large piston engine aircraft, as I recall he finished up on DC-7C, and was, at the time, one of the victims of the introduction of the "Age 60" rule by Pete Quesada, first FAA head honcho.

Back to "on the step", early editions of A.C.Kermode, "Mechanics of Flight" had a good treatment of the subject, for piston aircraft, some of the original graphs have slipped out of the later revised editions, as the emphasis has rightly changed to jets.

If you can find them around, the old "Pan American Navigation Service" textbooks on the subject provided some excellent coverage, with actual examples for the DC-4 and DC-7C. Sadly only of historical interest now.

Of course, it is quite (theoretically) correct to describe the "peak" performance of an aircraft, but in the real world of older airlines etc, the peak of L/D curve was so sharp that there was no speed stability, hence the invention of "long range cruise", a speed equivalent to a loss of 1% of max. range, in the interests of not driving the Flight Engineer crazy, ( and keeping the passengers on the edge of their seats with constant power changes).

As for the info. on boundary layer adhesion, the paper came from RAE Farnborough research, early to mid. 70's, I wouldn't even know where to start looking amongst 40 years of accumulated "items of interest" filed for Ron, Later Ron.

stator vane
1st Aug 2001, 11:58
mr. VMU;

regardless of what you said, i will stay with the old dino's that mention "the step"

perhaps not proper terminology, but the event actually happens on a regular basis.

you get the jet at cruise, especially heavy and 2000 feet above your optimum as Boeing recommends if there is a chance to get stuck at a lower altitude if you don't take this one now. and with the changes in CG as all the trolleys and slightly heavy cabin crew move around along with heavy passengers, and add that to headwinds, small gusts of turbulence, and tired autothrottles and autopilots and you can watch the aircraft slow and the nose pitch up to hold altitude. and it will sit there on the backside of whatever you want to call it!

and one either must make a PA and have lots of people move aft, or add some thrust to push the aircraft back over the whatever you want to call it, to get it back to where it should be.

i fly a 737-300/400 and have seen it happen for all the years i've been in both seats. and i can imagine that with the even longer 747's that it can be more pronounced, much more with the older big iron models.

please don't imply the older pilots are uncommonly ignorant, (and not just because i am becoming one myself-older that is)

a comparison, though limited, could be my considering you to be "ignorant" because you don't know the proper terminology of all the processes that occur in you hands and fingers and allow you to use them like you do. but you know when they hurt and how you have to change your method of operations to achieve certain moves.

we are all ignorant about a lot of things. so when one "ignorant" person calls another ignorant person, "ignorant", i laugh.

and don't ignore the increased instructions and terminology you might have received over the instruction that we older guys were given. and the very real change in aircraft characteristics! i was told to fly the airplane and let it teach me what i really needed to know. terminology is just another tool.

we can all learn from each other. i see older pilots and i want to learn all i can from them regardless of the lack of terminology. and when i see a new pilot with 300 hours join me in the right seat, i also want to learn from him/her some things that i may have forgotten or even didn't know that i didn't know.

RRAAMJET
2nd Aug 2001, 03:45
VmU:

as 411A mentioned earlier, the L-1011 had a most noticeable "step", at around .86M. The FE's used to love demo-ing it with the appropriate power setting, and it would cruise there with no noticeable slowing-down for ages, at the same FF as LRC. Had me baffled....I thought it was a wive's tale...

There was an interesting discourse on this in "Flying" recently, in a column by Peter Garrison. Someone from Edwards AFB sent in part of the a/c handling notes from the B-50 (B-29), describing in great detail how to get the a/c to cruise on the "step". :)

411A
2nd Aug 2001, 07:05
Two aircraft that I have flown previously, the DC-6 and the F.27 (and FH.227), achieved much better cruise performance if climbed (for example) 200 feet higher than the desired cruise level and then slowly descended while accelerated to the desired cruise airspeed. This works for light piston twins as well, especially if at higher weights.
It may come as a big surprise to the younger set to realise that large 4-engine recip aircraft were always cruised at a constant power setting rather than a constant airspeed, unlike jet aircraft.

Vmu
2nd Aug 2001, 19:15
If so, can someone please tell me why;
1. If a specific procedure(getting on the step) could increase the cruise-performance of an airliner significantly, why doesn't manufacurers tell us about it?
2. Why is there no sign of speed instability around cruise speed? There should be, if drag decreased with increasing speed.

I realize of course that if you fly a speed close to, or below mininmum drag speed, there would be "a step" (in holdings, for example).

BTW I fly F50's, basically a F27 with new engines. It does not have a step.

quid
3rd Aug 2001, 02:46
Thanks for all the posts. FWIW, here's my opinion.

After reaching cruise altitude, set symmetrical “Cruise Power” on all engines. Disconnect the autopilot and trim the aircraft for the existing conditions. If this is not done, it may take more power than necessary to hold cruise Mach.

The autopilot will only trim the stabilizer when a certain force is held on the elevator for a preset period of time. If this force value is not met, the autopilot will hold elevator pressure to maintain altitude. This out of trim condition, with its’ increased power requirement, might give the impression that the aircraft is not “on the step”. If allowed to accelerate to a speed faster than LRC, at some point where the preset force value is reached, the aircraft will now re trim and the thrust required will be less. This phenomenon may be the condition that perpetuates the myth of being “on the step”.

If you level off with autopilot and your autopilot trim system works this way,(and most do), it's pretty easy to think there's a "step".

stator vane
3rd Aug 2001, 12:12
first;

from the last reply from quid who started the thread;

good point about the limitations of the auto-pilot.

secondly;

as i look through my performance section of Boeing's D6-1420 manual about jet performance, which i copied while no one was looking, and somehow lost the first page with the proper title,
i see that in the cruise section, ALL the types of cruises; constant M and W/d, constant altitude (for max range or long range cruise), constant M and altitude, and rated thrust, are shown with graphs that have CURVED lines.
so when someone uses the term "step" it is not entirely invalid. the analogy to the wave is visually shown in these graphs. and when you fly through it enough, you will indeed recognize that it is invisible water that you are going through. aerodynamics is very similar to fluid dynamics. many wing tests have been done in oil fluids.

thirdly;

when VMU said, to the effect of, "the thing i hate most is when my colleagues speak of the step"...and we see later that you apparently are right seat of a turboprop-

i am surprized at your attitude. not that i haven't seen it before, but i am always surprized at it. and have seen it in myself at times, but have had it broken after all these years at a high cabin altitude.

if i may be allowed to speak directly to this point, VMU, and you do have the choice to listen or even add my reply to the list of things you hate the most from colleagues,

that attitude is dangerous, especially in an aircraft.

we will never be able to READ all that we need to know about flying. there is a lot about JUST clear air turbulence that we still don't know about well enough to predict it reliably.

and the captain may be able to show you something without having a chapter and verse reference to prove it to your immediate approval.

with 12,600+ hours total time and 4600+ hours in the left seat of B737's, one thing i am dismayed at is first officers who will not listen.

i understand now why many captains simply sit quietly for hours and seem to enjoy just flying the airplane. if they are like me, they have made hundreds of attempts to show first officers something that could help, but over the years we have learned that he/she must first want to learn before he/she will listen, and that our unrequested assistance is not taken very well. so we stay quiet until asked, or paid to instruct.

when i was in the right seat, i watched everything a captain did and took mental notes and sometime written notes. and i asked lots of questions.

now in the left seat, i show the first officers the best of what i have learned, and tell them, if there is anything i can help you with let me know. or after they have f..ked it up well enough that i must do something, i tell them what they could have done, thinking that if they want to listen, they will ask.

don't mean to berate at all, just a suggestion. and the subject was a smoking gun when i read this thread after two days with a 800 hour first officer who thinks he knows it all. but his flying gave irrefutable proof that he didn't. and after parking, when i told him what he could have done, he started arguing. i told him that he needed to stop talking and listen and watch the end product of his method of flying.

and these type of first officers actually think that we are required to let them fly the airplane????

why should we?

i will go quiet now about this.

i am listening.

stator vane

cosmo kramer
4th Aug 2001, 00:05
"Two aircraft that I have flown previously, the DC-6 and the F.27 (and FH.227), achieved much better cruise performance if climbed (for example) 200 feet higher than the desired cruise level and then slowly descended while accelerated to the desired cruise airspeed."

Why not just let the aircraft accelerate in level flight with climb power? Why the need to climb and descend first?

pigboat
4th Aug 2001, 02:09
Dunno about the six, but climb power is cruise power with the F-27, depending on engine -# of course. The 529-7E climbs and cruises at 14,2000 RPM and 730 TGT. :)

411A
4th Aug 2001, 04:06
CosmoK---
Descend at climb power to achieve better cruise airspeed. Works on the DC-4 and DC-7 as well. But, oddly, not on the L-1649A Connie. Did not get to fly this model all that long as the chief pilot crashed it at SCK. Tried a short landing and tore the gear clean off.

Pigboat--
Yes indeed, same on the 532-7 powered aircraft, except that if desired, cruise at 742C altho hot section longevity is not enhanced. :mad:

stator vane
4th Aug 2001, 07:00
okay, this seems to be an insider's thread.

i backed up the "step" captains with the two longests replies on this thread and get ignored.

i'm taking my toys and going home.

411A
4th Aug 2001, 08:57
Whoa, stator vane, don't run off just yet.

Would have to agree with you about some F/O's, all mouth and no brains. Fortunately they are in the minority.
Example-- high station outbound on the Kos vor approach, and sunnyboy in the right seat has now suddenly "forgotten" about proper configuration and speeds, and on final appears to delight at diving for the runway.
And this in a TriStar. Parked at the gate, his highness says...."well, that was not all that bad, was it Captain?" After more than 10,000 hours in the L10, I have to admit that he was positivly the worst that I have seen, and this includes ten years in SV. 'Course, according to him, he was ace of the base.
:rolleyes:

stator vane
4th Aug 2001, 11:51
411;

thanks for the response.

sometimes i wonder if i am from another planet.

it feels like it sometimes.

probably was in a bad mood last night.

southwest airlines told me NO for the second time.

they will not get another chance.

4500+ hours in the left seat of a B737 with no scratches and they say NO. they must want some shiney buttons that will always say YES or somebody who knows somebody.

this interview thing is worse than dating girls.

maybe i said something about being on the step during the interview.

quid
4th Aug 2001, 22:34
Sorry to hear aobut the turn-down, stator vane. Hang in there.

I'm part of the hiring process at my airline, and I'm frequently PO'd at the results. Human Resources has veto authority and there is nothing we (flight ops) can do about it. We've lost some damn fine pilots because of HR. That's life in the majors today.

pigboat
5th Aug 2001, 05:55
Welcome back, stator. I thought your posts were to the point. Sorry if I gave the impression of trying to create anything other than a straight statement of fact.
Some people may learn from it, some may not. Call me cynical, but I don't much care one way or another.

stator vane
5th Aug 2001, 11:47
i need to get a life!!

last night i woke up thinking of this "on the step" thread.

i could see it as a picture of our learning process in flying. (and every other part of our lifes) we have to go a little beyond our present capabilities and then settle back down on the right side of the "step"

and there seems to be a fine line between confidence and arrogance. if we think we are a bit above everyone else and better, it usually isn't long before some "turbulence" comes along and if we are really smart, we settle back down a bit and achieve a balance of confidence.

and at least for me, when i am in the air, i realize that there have been many times that those who were a lot better than i could ever be, have encountered things that were beyond their capabilities. and in that confidence that we all have should be a little package of caution since we move in a medium that still has some unseen surprizes.

"on the step"

i remember when i was flight instructing in alaska, that i was reprimanded by the operator for making my INITIAL students read accident reports. i wouldn't stop doing it. i thought that from the first day, they needed to realize that they were starting an endeavor that definitely had some hazards and that these accident reports will explain why we instructors were so adamant about certain things.

on the step in a risk management endeavor.

john_tullamarine
5th Aug 2001, 13:01
If I may make a couple of brief observations.

As a first approximation, cruise performance is a matter of thrust minus drag. If one approaches the desired cruise speed from below with the book thrust figure, then one would never quite get to the target speed as there is a need for a bit of excess thrust to do so.

Conversely, if the speed is approached from above with the nominated cruise thrust set, then speed will progressively decrease to and, usually, slightly below target speed as the atmospheric bumps and thumps take their toll. It is a bit of a battle on a small scale. Depending on the state of the air mass, this might occur comparatively quickly or slowly. Also the particular drag polar shape will influence the degree to which the effect is seen.

Whether you get into the initial higher speed state by using excess thrust or descending from a slightly higher level is immaterial.

I have always presumed that this phenomenon is what people mean when they refer to "the step" although, clearly, the term is an historical reference to flying boats and planing speedboats and the like as one of our colleagues observed in an earlier post.

I fail to see why it is something which people get excited about. The manufacturer gives us a bunch of numbers for performance and the ops engineers monitor and, if necessary, modify the figures for individual aircraft in line service.

Within the constraints of practical operation, we can probably squeeze a few knots out of the old girl from time to time - but it is a small matter.

Some aircraft, such as the F27, have a quite pronounced "low drag bucket" in the drag curve shape in the region of cruise alpha for all the obvious reasons. The term is quite apt as the curve has such a shape.

stator vane
6th Aug 2001, 22:30
"the term is quite apt as the curve has such a shape"

amen
a drink for all the "on the step" dino's!!! on me.

:p

Nick Figaretto
8th Aug 2001, 06:12
Step or no step:

Stator vane: What are you, some kind of hobby-psychologist?

Just because an FO doesn't "believe" in your beloved step, doesn't mean he's unable to take any advice or helpful hints that his more experienced FC is providing him with.

...that attitude is dangerous, especially in an aircraft.

WHAT ATTITUDE? The "I have a brain, and can think for myself" -attitude?

I understand that you have had some bad experiences with your FPs, but you must surely have had some bad experiences with your FCs over the years too. If you're able to look that far back...?

I always try to learn as much as I can from my very experienced captains. Nevertheless I am equipped with something called sound judgement. I let most of the hints and advices I recieve become a part of my flying skills and experience. But some of them I reject, because my own sound judgement and gut feeling tells me to.

I had a captain who adviced me to pull the throttles "just a tiny bit" into the Beta-range if we were hot and high. :eek:

Judging from your reply to Vmu, you'd expect me to "buy" everything any FCs tells me. What kind of attitude is that? What do you think you are: "God's gift to aviation"? Just because you have this "step"-thing all figured out?

Of course there are FOs that do stupid things, due to their lack of experience. (That's why they are FOs, isn't it?)

But there certainly are FCs around who's only merit is the number of flight hours in their log book. And not much more.

There are plenty of others in this forum who disagree with you on this little "step"-debate. Why let go of all your supressed anger on an FO that disagrees with you, just because you are obviously having your period?

So please: Pick on someone on your own size.

And don't jump to conclusions.

I hate that.

Nick.

Vmu
8th Aug 2001, 15:51
I wish i had not written the "i hate" part of my first post. To sound arrogant or provoke anyone was not my intention. It has also caused this thread to drift away from the topic.

John_T: You seem to be the first engineer on this thread. A couple of questions; Isn't a "drag bucket" on the drag vs alpha curve rather normal on modern airfoils? As far as I know this does not imply that there is a "bucket" in the drag vs airspeed curve. The way I understand the "pro step" people, they argue that there is a bucket in the drag vs airspeed curve giving lower( or perhaps equal) drag as airspeed is increased. Have i understood things correctly?

john_tullamarine
9th Aug 2001, 00:03
I only mentioned the situation on the F27 as I did a study on that wing many years ago and it was mentioned in an earlier post. I have no position regarding "the step".

[ 08 August 2001: Message edited by: john_tullamarine ]

stator vane
11th Aug 2001, 00:39
Vmu;

i will make a public apology for as figaro described as "picking on you" if that is how you took it.

the thread started as a question about "on the step" and it's validity. your response went into another area of how you were embarrassed by those captains who used the term and that it indicated their ignorance of performance.

my response merely aimmed to point out that implying that your captain is stupid for using a terminology that may not be so precise yet does indeed describe a valid description of curves and lines and actual experience in the aircraft, could be dangerous in the aircraft. he may actually have a large amount of experiential knowledge about performance without having the terms used in books.

and as figaro pointed out, accepting everything he or she does or says can be just a dangerous.

so i hope you accept my apology.

and to quid, at least i made a small contribution to your thread earning that much coveted flaming folder.

cheers;
:)

quid
11th Aug 2001, 07:59
OK, guys and gals, it's been two weeks, and anyone interested has had an opportunity to respond.

Now (for what it's worth), let's take a vote:

Flying a swept wing transport jet at cruise altitude, IS THERE A "STEP"?

Yes or No?

411A
11th Aug 2001, 08:56
...NO

Stage3
12th Aug 2001, 04:51
Are you all serious?

quid
12th Aug 2001, 08:27
warpfactor8,

I can't speak for the others, but I certainly am.

Do you have something to offer in the way of an opinion/explanation?

[ 12 August 2001: Message edited by: quid ]

GlueBall
14th Aug 2001, 05:56
...there is an "invisible step." It's in cruise at altitude. If you fly less than LRC the airplane is not optimally speed configured because the deck angle is too high and you can feel it as you leave and reenter the cockpit. Flying less than LRC is neither fuel efficient nor aerodynamically efficient. :cool:

quid
14th Aug 2001, 06:46
GB-

I don't think anyone doubts that at speeds LESS than LRC, you really cut down on the NAM per fuel unit. You can stay aloft for a longer period of TIME, tho.

It's the "step" FASTER than LRC that's in question. IE, if LRC is M.79, then getiing it up to M.80 or .81 and then pulling back the power to LRC settings, you'll be "on the step" and get better results than LRC.

cosmo kramer
16th Aug 2001, 14:59
Hello I have never flow jets and never will. But don't you think that would be mentioned in the manual if possible? Not to mention the bean counters would probably have all their pilots go through a "step test"? :D

john_tullamarine
16th Aug 2001, 16:50
Quid's comment is pertinent.... we are talking about a poofteenth of cruise speed.
A spot of turbulence and it evaporates. That is, the whole idea is fun, but not really worth wasting the time on it....

Herc Jerk
16th Aug 2001, 19:43
Never found any "documented" proof about the step.

But hell, i still do it because it feels better :)

Kinda reminds me of something else...

bwahahahaha

Checkboard
16th Aug 2001, 19:54
Enough on this Old Wives Tale, I think!

Lets keep Tech Log to reasonably serious Tech Questions, in order to preserve the validity of the forum.