What was the typical climb/acceleration and cruise profiles in the 707,720,727,DC-8,DC-9, and the CV-880/CV-990? When were the flaps brought up (was it 1,000 feet like now, or was it another altitude)?

Andrea Kent

B707.

Started flap retraction at 800 agl.
Once flaps retracted, set climb thrust.
Accelerate to 300 KIAS for the initial climb.

B727

T/O power to 1000' agl
Quiet Thrust at 1000' agl
Flap retraction and accel at 1000' agl
Climb thrust at 2000' agl

Cheers,

John

411A, you're the guy who was the 707-320 Captain right?

Andrea Kent

Remember, fuel was cheap and traffic was light. Today, the thrust and lift values are all different and there is air traffic nearly everywhere.

Some consideration was given, a few years back, to doing away with the 250 kts below 10000' rule under the assumption that traffic could be expedited and fuel saved. In actuality, the departure flow rate could not be increased by changing the profile and fuel savings were not demonstrated.

Considering the complexity of many departure procedures now in use and the necessity of precision flight path performance, changing the climb profile might not be a good idea. Although much money was spent by the FAA studying risk models, they never fully considered the increased cost of and and rate of collision with wildlife nor the ramifications that increased speed in the terminal area would have on radar vectored traffic. In fact, they didn't realize that increased speed in low altitude terminal airspace might increase the rate of TCAS RA events.

Considering the cost of studying these additional factors, the experiments at KIAH were terminated and the matter dropped.

I got most of what you were saying, but "Thrust and Lift Values" I don't get. Modern planes have better T:W ratios than back then and more efficient wings for the same speed (an L-1011 or DC-10 for example can do 0.85 and has a far better T:W ratio than a 707-120)

Andrea Kent

Correct, Blackbird, a B707-320 Captain for 10 years.

An additional note:

IF a noise abatement climb was required, the 707 profile was...

Takeoff thrust to 1500 AGL, climb thrust selected, climb at V2+10 to 3000 AGL, flaps retracted, accelerate to 300 KIAS.

Does anybody know what the DC-8's, and the CV-880 and CV-990's climb and acceleration pattern was?

Andrea Kent

411A,

Just curious... when you say flaps retract at 800 feet... does that mean you start to retract at 800, or you have them all up at 800?

Andrea Kent

With the B707, flap retraction started at 800 agl (completion of the second segment of the takeoff flight path).
Some operators adopted a flap retraction height of 400 feet, which was the minimun under CAR4b.
Minimum flap retraction speed, V2+30.

411A,

You used Flaps 25-for takeoff right, then at 800 went to Flaps-17 (I think the -320's used 17-degrees, and the -120's 14-degrees), then up right?

Pulling the flaps up that early (400-feet) would probably be to get the plane up to a high-speed nice and quick, right? May I ask what airlines adopted such a regulation?

From what I remember, there were at least some airlines that sometimes took the climb-speed up to 335 kts even with a 707-320/707-420. I know almost certainly that some operators took the 707-120's at least right up to 350 kts.

Andrea Kent

Itr depended on the specific airplane, Blackbird.

Example.

B707-320B
Takeoff flap settings were either 14 or 17 degrees, depending on the specific model.
So, flaps retracted at V2+30.
And, quite unlike the B747, the leading edge devices all retracted at the same time.

---OR---

B707-320 (non-fan) straight pipe engines.
Normal takeoff flap was 20 degrees, so, flaps were retracted at V2+30, the same as the -320B airplane.
However, shorter runways required a flap 30 takeof, so, flaps were selected to 20 degrees at V2+10, than at V2+30, flaps fully retracted.

AirFrance used flaps up at 400 agl, as did BOAC.
However, later on, upon a Boeing policy/approval, 800 agl was adopted.
Having said this, 400 agl was still the certification standard, but airlines were permitted to adopt 800 agl if they so desired.
Runway analysis/climb charts were altered as necessary.And finally, with the B707-320B airplane, a flap 25 takeoff was NOT allowed...because, these aiplanes were equipped with an improved flap design.

Flap 25 was used, however, for circling approaches, until on final, whan flap 50 (or 40, for noise abatement) was selected.

You learn something new every day. I always thought Flaps 25 was used for virtually all takeoffs... I guess it was just a 707-120/120B/ and occasionally -320 (Turbojet) thing.

So landings were typically Flaps 50-affairs unless noise-abatement was an issue? Also, how common would you say noise-abatement proceedures were used?


Andrea Kent

Noise abatement takeoffs.

With the B707, these were done at airports that so specified a noise abatement procedure.
Climb at V2+10 to 1500 agl, climb power selected, then climb to 3000 agl, where flaps were retracted at V2+30, then acceleration to enroute climb speed....normally 300KIAS/M.80.

Noise abatement landings.
These were done at selected airports, as specified by the airline (only PanAmerican so specified, oddly enough), and the final landing flap selected was 40 degrees.
This required excess runway to be available, typically 800 feet...more.
Threshold speed, minimum Vref+10.
IF significant crosswinds were present on landing, flaps 40 was also approved for landing, in lieu of noise abatement procedures.
All subject to Captains decision.

At some airports, where a thrust cutback procedure was mandated on takeoff, the following was accomplished:
Takeoff thrust to the noise critical point (usually about 2NM beyond the end of the runway), thrust reduced to enable the dB meter not to be pegged, and once this point was passed, takeoff thrust reselected, and climb to 1500 agl, where climb thrust was selected, followed by a climb to 3000 agl, where flaps were retracted.
London Heathrow mandated this procedure with non-fan airplanes, as did FRA and ZRH.
Note that during the thrust cutback maneuver, no positive climb was expected nor achieved...just less noise.

No such rule exists at some airports like Singapore, common to do 280-330 kt below 10,000.

The 800, 1500, 3000 feet noise abatement heights above are still the standard today.

Quoting Boeingfixer (Reply 2): Quiet Thrust at 1000' agl

'Quiet thrust'? Sounds like an oxymoron, especially when talking about the 727 and modern noise regulations.  

-N243NW 

Quoting 113312 (Reply 4): Some consideration was given, a few years back, to doing away with the 250 kts below 10000' rule under the assumption that traffic could be expedited and fuel saved. In actuality, the departure flow rate could not be increased by changing the profile and fuel savings were not demonstrated.

In fact the departure flow rate leaving those airports in Houston, primarily IAH was increased over what is able to be put into the sky today! The tower controllers could get the aircraft airborne faster on the same routes knowing the departure controllers had another tool at their disposal.

Sort of difficult to quantify what you saved fuel and time wise but I will tell you this, there were far fewer vectors issued for spacing during the demonstration than either before or after. So, for there not be be savings in fuel and time enroute is hard for me to grasp since you were not getting the daisy chain started that almost every departure rush seemed to get going, but you had a more direct route out the departure gate. Aircraft were able to climb at their desired flight plan speed in most cases which was efficient, and not be restricted to 250 KIAS until reaching 10,000' MSL, funny thing, most had a much better angle of climb at the higher speeds.

Quoting 113312 (Reply 4): Although much money was spent by the FAA studying risk models, they never fully considered the increased cost of and and rate of collision with wildlife nor the ramifications that increased speed in the terminal area would have on radar vectored traffic

Interesting that you mention wildlife, I guess the Canadian geese don't fly on the departure routes in Canada like here in the U.S........and there was during the Houston demonstration 1, only 1 reported bird strike when an aircraft was above 250 KIAS climbing, yes there was cost associated with that aircraft flying into a flock of geese, but had they been flying faster than the reported speed they were, that particular plane would have been long gone when those geese appeared in that location! 

I am at a loss to understand what the ramifications are in the terminal area for vectored traffic, please elaborate.

Quoting 113312 (Reply 4): In fact, they didn't realize that increased speed in low altitude terminal airspace might increase the rate of TCAS RA events.

Incorrect. It was thought of, reviewed during and after the demonstration.....zero TCAS events reported as a result of higher speeds, zero NMAC's filed as a result of higher speeds, no pilot deviations as a result of higher speeds, and no controller error as a result of higher speeds.

Quoting 113312 (Reply 4): Considering the cost of studying these additional factors, the experiments at KIAH were terminated and the matter dropped.

The costs for studies that some organizations demanded from the FAA were factors in the demonstration being terminated. What better study than millions of departures leaving town to validate a study! However, it was more the FAA crumbling to pressure from some Washington DC groups demanding the demonstration be stopped.....and actually during the last 4 months noise is circulating once again to revive the program. BRAVO

For those controllers who worked the traffic during the more than 7 years the demonstration was being used will tell you, if you didn't give it to the pilot most would ask if they could delete the speed restriction!

Quote: Noise abatement takeoffs. With the B707, these were done at airports that so specified a noise abatement procedure. Climb at V2+10 to 1500 agl, climb power selected, then climb to 3000 agl, where flaps were retracted at V2+30, then acceleration to enroute climb speed....normally 300KIAS/M.80.

That's just climb-speed right? I always thought 707-320's cruised at Mach 0.85

What airline did you fly for 411A, if I may ask?

Quote: At some airports, where a thrust cutback procedure was mandated on takeoff, the following was accomplished: Takeoff thrust to the noise critical point (usually about 2NM beyond the end of the runway), thrust reduced to enable the dB meter not to be pegged, and once this point was passed, takeoff thrust reselected, and climb to 1500 agl, where climb thrust was selected, followed by a climb to 3000 agl, where flaps were retracted. London Heathrow mandated this procedure with non-fan airplanes, as did FRA and ZRH. Note that during the thrust cutback maneuver, no positive climb was expected nor achieved...just less noise.

I wouldn't be suprized. Those JT3C powered -120's and JT4A powered -320's were so underpowered by today's standards. I guess that the cut-back maneuver was done to reduce noise over populated areas, and then once in the clear, you guys brought the thrust back up to normal climb-levels.

Oh, one other question... I remember some guy told me (he obtained this info from a retired airline pilot) that sometime after climb-power was set, they would increase the power levels to MCP, or near such levels of thrust and would perform some type of cruise-climb (Back in 1959 to 1962 about from what I was told). Additionally, I remember reading something about the CV-880's crews talking about pushing the throttles up once through 10,000 feet.

Is there any truth to this/these statements?

Andrea Kent

Answered in order received...

B707's did not cruise at M.85....far too fast, for the design.
M.82 was normally used, M.84 on occasion, at lower levels (FL280) if one were late with the schedule.
Long range cruise, M.81

Singapore Airlines.

Max cruise and/or max continuous power was almost never used (not by me, anyway).
With these airplanes, both fan and straightpipe powered, it was found that by staying lower, and using normal cruise thrust (versus higher, at MCT), fuel could be saved and engine life extended.

In addition, some might say...well, the B707 had a 35 degree sweepback, so it should have gone faster.
Ordinarily true, however, the airfoil section used had pronounced mach tuck beyond M.84, and needed conderable additional downforce generated by the horizontal stabilizer, which added up to a lot more thrust to overcome this condition...read, big fuel bills.
Bad for the airline bottom line.

OTOH, the airplane I fly now, the Lockheed L1011, has a true high speed wing, and cruises comfortably all day long at M.85...even M.865, if I so desire, and quite efficiently.

[Edited 2007-04-17 00:17:57]

The L-1011's a great aircraft. Sadly there was no real rival to the DC-10-30, sure the -500 had the range, but not the same capacity (shorter fuselage), the -250 had the long body, and pretty good range, but still retained the -1/-100/-200's wingspan, and it's range was not quite as good as the -500.

What model of the L-1011 do you fly, 411A?


Andrea Kent

Blackbird, I presently fly both the -100 and the -250....nice airplanes.

The -250 is a great jet, the closest long-bodied rival to the DC-10-30. I've flown on a couple of -250's during the late 1990's. Back then they were flying for Delta Air Lines.

BTW: I do remember flying on two particular L-1011's, not sure if it was the L-1011-250, or another plane (DFW-HNL and HNL-LAX), but those two flights stood out uniquely because they were loud as hell. When the engines were idling and during taxiing, the noise levels rivalled a typical plane during flight. During takeoff the plane rattled like hell, and in flight the noise levels were loud as hell (It was mostly a suprize, although, excepting the rattling, cool on the ATL - HNL flight; it was annoying as hell on the flight from HNL -LAX since it was a night flight and I had planned to sleep then), although on other L-1011 flights the noise levels were quite reasonable. I figured some of them were really old and their sound-proofing was breaking down. Are any of the -100's and -250's you fly like that (like those really loud two that I flew on)?

Andrea Kent

I do fly ex-DAL airplanes, Blackbird, and we have no problem with excess noise.
By the way, only Delta had -250's (six in total) as they converted 'em right in their hangar at ATL.

I guess the noisy L-1011's I flew on did not include any of the -250's then. I have flown on an L1011-250 on at least a few other occasions-- they were normal in terms of noise. I know Delta converted four -1's to -250. Prior to that point though, two were built as L-1011-250 from scratch... equalling the total of six.


Andrea Kent

IAHFLYR,

AAAaaahh, the "no speed" days! but the ERJ wouldn't do it until 8500 from the software, and then it might be at 265 at 9700' if whipped...No guts; but an honest a/c...

Quoting Blackbird (Reply 23): I guess the noisy L-1011's I flew on did not include any of the -250's then.

You were probably on one of the older airframes that did not have the "Frisbee" fairing attachment to the No.2 engine, which was developed by Lockheed at the time of the L-1011-500 and was effective in engine noise reduction.

I'm not sure if it involved the noise-attenuating S-duct fairing or not. Because from what I was told from day one, the L-1011 was at least as quiet as the DC-10. I've flown on DC-10's too, and I'll tell you they were nowhere near as loud as those two loud L-1011's that I flew on. Not to mention, to my knowledge, didn't all of Delta's L-1011's get re-fitted with those noise-attenuating fairings? I know TWA did such a refit. I think it was more a matter of noise-insulation breakdown to be absolutely honest. Could be wrong.

Andrea Kent

I had a similar experience on a TWA L-1011 in the mid-90's. I was on the port side of the aircraft on the trailing edge of the wing. Taxi noise was not particularly onerous (and we had a lot of it as we taxied for an hour at STL awaiting departure to LAX). But takeoff thrust noise was eye-jiggling. And even in cruise, the sound was perfectly thunderous. The plane was nearly empty and I should have moved around to see if the sound changed.

I think it's an acoustic absorbing material breaking down inside the plane.

Andrea Kent

Quoting Blackbird (Reply 26): Not to mention, to my knowledge, didn't all of Delta's L-1011's get re-fitted with those noise-attenuating fairings? I know TWA did such a refit. I think it was more a matter of noise-insulation breakdown to be absolutely honest. Could be wrong.

I don't know the exact numbers but I believe less than half of the L-1011 fleet had the noise reduction fairings. The only aircraft to have the fairings were the L-1011-1's delivered in the early 80's and of course the whole -500 fleet as well. The ex-EA fleet did not have them nor did the older -1's delivered to DL in the '70s. TWA was the only airline to opt for a complete Frisbee fairing re-fit.

Either way, back to the original topic...

I was curious what the climb and acceleration pattern of the CV-880 in addition to the 707 and DC-8. Because I want to fly it in FS just like how it was really flown back in the olde-days.

The way I do it currently is rotate, gears-up on positive rate of climb, V-2, V2+30, take her up to 400 feet, flaps up, go to 800 feet before reducing to climb power. Generally I try to get to 400 kts as soon as possible, hold that until Mach 0.91 comes up on the climb, and just hold that the rest of the way. On the way down, hold .91 until 400 kts comes up on the speed gauge, hold that speed all the way into the downwind leg, then begin slowing down.

Sounds absolutely insane, but I think that's how they really flew it! Any verification / non-verificiation here?

Andrea Kent

Just a tad insane, Blackbird, when one considers that the CV880 has a Vmo of 373KIAS, and an Mmo of .884.
Friends that have flown the 880 tell me that the standard profile for climb was 320KIAS/M.82.

Normal cruise speed M.84.

I guess the dynamics of the model I'm flying aren't all that good! Although keep in mind it was a FS model!

Andrea kent

BTW, I've e-mailed the guy that created the flight dynamics for the CV-880 model I was flying informing him of the various errors.

Either way, I've checked some online sources and you're right about the Vmo being 373 kts, interestingly due to it being an *old* plane, the old outdated speed-gauge reads 393 kts at around 21,000 feet due to some kind of compression effect (a modern airplane would be calibrated from what I've been told in the Airliners.net chat to not read such false-readings) Either way 393 kts have been listed often as a top-speed in many sources, which might have ended up as a 400 kt listing.

In either case, a guy who worked on the CV-880 restoration project told a friend of mine that they often did fly into the pattern doing speeds of around 400-kts. I guess the overspeed warning was sounding all the way, but it does appear to have been done actually. The CV-880 was extremely sturdy and could take substantial aerodynamic loads. Supposedly a CV-880 sustained 6-G's during a training mishap, and was not damaged in any significant way.

Andrea Kent