Mr.BA
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Some Questions On The B767 And A340

Wed Apr 24, 2002 7:36 pm

Hi guys,

Hope someone can help me here. I'm interested to know! Maybe Rick 767 can help me with the B767 and Skystar on Airbus?

-Average fuel burn on the B762/3?
-MTOW of the B762/3?
-Mmo and Vmo of the B762/3?
-Average cruising Mach for the B762/3?
-Rate of fuel dump of the 762/3?
-Average Take-off trim setting for the 762/3 at or near MTOW?
-Maximum fuel load on the 767-300/B767-300ER?
-what's the overweight landing flap setting on the 767?

-Average fuel burn on the A340?
-MTOW of the A340?
-Average cruising Mach for the A340?
-Rate of fuel dump of the A340?
-Average Take-off trim setting for the A340 at or near MTOW? Airbuses have auto trim?
-Maximum fuel load on the A340-300?
-what's the overweight landing flap setting on the A340?

Thanks a lot everyone!

alvin

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Rick767
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RE: Some Questions On The B767 And A340

Wed Apr 24, 2002 8:18 pm

Average fuel burn on the B762/3?

For the 767-300 - 2,200 kg/hr per engine = 4,400 kg/hr is the company documented average, goes up to about 5,400/hr at FL310 (MTOW) down to about 4,000 kg/hr towards top of descent up at FL370/390.

MTOW of the B762/3?

762 - 159,210 kg
763 - 186,880 kg

Mmo and Vmo of the B762/3?

Vmo - 360 KIAS
Mmo - Mach 0.84

Average cruising Mach for the B762/3?

Variable and dependant on cost index, but M0.80 is what my airline tends to stick with, fraction less on the eruopean trips (0.79ish). Not really worth going up to 0.82 even when running late due to the reduced fuel economy.

Rate of fuel dump of the 762/3?

1,200 kg/min

Average Take-off trim setting for the 762/3 at or near MTOW?

Not got figures to hand.

Maximum fuel load on the 767-300/B767-300ER?

763ER - 77,750kg
Dunno about the -300? Anyone?

what's the overweight landing flap setting on the 767?

Depends how overweight you are, Flap 25 normally due to Flap 30 LRS activity @ higher speeds. If VRef + 5 + gust factor comes to less than 170 knots we can go with Flap 30. Nice to have some more comfort if it's close though. Flap limit speed for Flap 25 is 180 KIAS and the Vref only increases by 3 knots from memory from Flap 30 to Flap 25.
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cv640
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RE: Some Questions On The B767 And A340

Wed Apr 24, 2002 10:10 pm

Was the 767 MMo changed t .84 recently? The number that I have is .86 for both the 757/767.
 
Rick767
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RE: Some Questions On The B767 And A340

Wed Apr 24, 2002 10:34 pm

typo... M0.86 for the 757 & 767.

Rick.
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flysab
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RE: Some Questions On The B767 And A340

Wed Apr 24, 2002 11:16 pm

And here are the answers for the 340-300.
Average fuel burn : count on 10 tons for the first hour, then 6 tons/hour
MTOW : depending on certification : 257 or 271 tons
Average cruising Mach : .81/.82
Rate of fuel dump : advertised by Airbus as 1 ton/minute
Max fuel load : 109589 Kg based on a fuel density of 0,785 kg/l
Overweight landing flaps setting : Full unless acft weight is above the max weight for go around perfo, which is given in a table. The setting will be given by the ECAM in function of the failure leading to the overweight landing.

Hope this helps you.
 
rmm
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RE: Some Questions On The B767 And A340

Thu Apr 25, 2002 12:02 am

Did the 762 have a fuel dump system? Never seen one.

Rmm
 
HAL
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RE: Some Questions On The B767 And A340

Thu Apr 25, 2002 1:09 am

Here's the info for the 767-300ER in our (Hawaiian) configuration.

Avg. fuel flow @ mid-weight about 6000 pounds per hour per engine. (Pratt engines). After max weight TO, initial cruise at FL330 would be at 6750 pphpe. At end of cruise at light weight (260,000 lbs) at FL410 fuel flow would be 4428 pphpe.

MTOW 408,000 lbs

Mmo .86
Vmo 360 kts

Avg. crusing mach .79 - .81 for transpacific

Fuel jettison rate 2600 lbs per minute

Trim at TO avg. 4 - 7 units

Max fuel load 23,980 gallons or 160,666 lbs

Overweight landings are made at flaps 25 if the weight is greater than 360,000 lbs. (Normal max landing weight is 320,000 lbs)

HAL



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Rick767
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RE: Some Questions On The B767 And A340

Thu Apr 25, 2002 1:40 am

No fuel dump on our 762s, but then it's a customer option on all 767 models so I'm not sure..

There are plenty of -300s out there with no fuel jettison too....

Also with regard to the overweight landing it seems that Hawaiian base the weight over which Flap 25 is used on a Flap 30 Vref of 160 knots or more (giving a 10 knot margin on the maximum flap 30 operating speed).

This is also 163,000 kg on our 763s (equivalent of 360,000 lbs). Our company SOPs for the 763 state that

"...it may be necessary to land at Flap 25 if the planned approach speed comes close to the Flap 30 speed limit of 170 knots to avoid Flap LRS activity"

So it appears we get a bit more freedom to choose our flap setting at the more marginal weights around 163 tonnes, depends really what the Captain defines as "comes close to"!

Hope this was of interest.
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HAL
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RE: Some Questions On The B767 And A340

Thu Apr 25, 2002 4:07 am

The four 763's we're getting from LTU do not have the fuel jettison option. The other 12 new ones do.

And yes, our manual states in the 'overweight landing' section "To prevent possible flap blow-up at higher approach speeds, flaps 25 are required when landing weights exceeds 360,000 pounds".
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Mr.BA
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RE: Some Questions On The B767 And A340

Thu Apr 25, 2002 5:15 am

Thanks to all for the help!

Any idea what's the maximum pitch up angle for the A340/B767 on rotation? The climb pitch angle?

Off topic here, but would like to find out if there is any way to calculate approach speeds for approach in gusting tail wind? I believe you Wind - simply half the wind speed plus the full gust added onto your Vref up to a maximum of Vref +20. (Not too sure if it's the same for the B767/A340)?

Thanks to all again!
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Rick767
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RE: Some Questions On The B767 And A340

Thu Apr 25, 2002 10:30 am

Rotation Pitch angle

On the 767-300 a tailstrike will occur at 8 degrees nose-up with main gear compressed and 9.5 degrees nose-up with main gear extended.

Especially important in a continued takeoff after an engine failure as the minimum ground clearance is just 12 inches and occurs just after liftoff.

Climb Pitch angle

This depends upon weight, flap setting and thrust setting.

Anywhere between 15 and 20 degrees nose-up to hold V2+15 on the climbout. Our ops manual states to hold a speed between V2+15 and V2+25 on the initial climb out (pre thrust-reduction / acceleration alt). There is very little difference in actual climb angle between those speeds (though the angle starts to reduce significantly climbing above V2+25).

Gust Factor

"Approach Speed" is Vref+5 in calm wind conditions. The gust factor applied is the difference between the maximum and minimum wind speed reported at the surface. In addition, half the headwind component is applied, with a maximum approach speed of Vref+15.

So Approach Speed = Vref+5+Gust Factor+Half h/w component.

The half headwind component is applied initially to counteract a reduction in gradient headwind as the aircraft descends through the shear layer close to the surface.
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Skystar
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RE: Some Questions On The B767 And A340

Thu Apr 25, 2002 4:39 pm

You can also get the 343 with a 275ton MTOW.

Max pitch on takeoff for the 343 is 10° (gear compressed)/14° (gear extended). Add two degrees for the 342.

Typically, climb pitch angle (ie. after rotation) is 12.5° on the A340. Just remember, it's not super well endowed with power, and takeoff flap settings aren't as low as those of twinjets (ie. Flap 1=17°, Flap 2=22º (which is Flap 3 on the 330), Flap 3= 26°).

Just to add to the 767 info, you'll get fuselage contact at 9.8° on the 763 & 13.1° on the 762 (gear extended).

Cheers,

Justin
 
GWB
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RE: Some Questions On The B767 And A340

Thu Apr 25, 2002 6:59 pm

Rick767,

I was scan-reading this thread and can't believe the depth of knowledge you have. It's incredible. How do you find time to give such detailed replies? Respect!

GWB
 
Rick767
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RE: Some Questions On The B767 And A340

Thu Apr 25, 2002 7:41 pm

GWB

Actually it's less fun than it sounds - I have been off work sick for the last few days home alone with a nasty head cold!

Once May comes around life gets pretty hectic...  Sad
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Mr.BA
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RE: Some Questions On The B767 And A340

Thu Apr 25, 2002 11:45 pm

Thanks everyone especially to Rick767 and Skystar for the excellent replies. That's what I'm looking for! Thanks again everyone, really appreciate the help.

Take care everyone. Especially Rick767, get well soon! Busy schedule for May?

Cheers!

alvin
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Rick767
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RE: Some Questions On The B767 And A340

Fri Apr 26, 2002 3:12 am

No probs alvin. Always glad to be of help! Starting to feel a little better now actually.

May is busy with work (just like every May seems to be!!) and I'm also moving house on the 4th.. such fun  Insane

Take care.
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Skystar
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RE: Some Questions On The B767 And A340

Fri Apr 26, 2002 9:20 am

You're welcome for the info, we should also thank FLYSAB for the other A340 info  Smile Not to mention HAL for the Hawaiian info as well. Hopefully Rick767 gets better.

Just on the 767 initial climb pitch angle (figures for S/L). On the 762, it can reach as high as ~23.7° (Flap 1, 109ton BRW), and be as low as 16.5° (Flap 20, 160ton BRW).

On the 763, about 21.2° (109ton BRW, Flap 5), or as low as 14.3° (186ton BRW, Flap 20; Flap 15 angle is quite similar).

With one engine out, pitch can range from just over 17° (762-F1), to 10.5° (763-F20).

Cheers,

Justin
 
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RE: Some Questions On The B767 And A340

Fri Apr 26, 2002 2:18 pm

Thanks FLYSAB and HAL too  Smile Should say "thanks everyone" so I won't miss out anybody as everyone did help me  Smile A few more questions I have managed to come up... I actually thought of them in my dreams, can you believe that!!??

How much can the nose gear of the B767s/A340s turn left/right on the ground while taxying? If full rudder is kicked into the same direction of the turn, how much more degrees can it provide to aid the turn?

Does the taxi lights on the B767 turns off automatically after the main gear leaves the ground (from ground to air sensing mode) like the B747s? I have seen a few Qantas B767s' taxi lights turns off automatically after lift-off.

Thanks everyone!

Cheers take care. Glad to hear you are getting better Rick767! Not inviting me to your house warming party? Big grin

alvin


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Skystar
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RE: Some Questions On The B767 And A340

Fri Apr 26, 2002 6:50 pm

If I recall correctly, the A340/330 will give about 70° nosewheel steering, however a few years back this was limited, as extreme angles of steering were causing extra strain on the landing gear.

Pushing the rudder pedals will not increase nosewheel steering angle, the tiller will give much more than the rudder pedals. Nosewheel steering via rudder commands is also cancelled above 100kts

Cheers,

Justin
 
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RE: Some Questions On The B767 And A340

Sat Apr 27, 2002 12:31 am

Alvin,

Now you're dreaming about the 767, that's worrying! Maximum nosewheel deflection is 65 degrees on the 767.

You've caught me on the taxi light one though, I have no idea. I guess they do go out with the air/ground logic (after all, that would be logical!).

Will dig out the tech manuals when I get chance and see what they say.

No chance on the house warming mate, I don't even think I would be able to arrange one before October the rate things are going... I hate moving! I'm really starting to crack up  Crying!!

Take care.
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flysab
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RE: Some Questions On The B767 And A340

Sat Apr 27, 2002 1:21 am

According to my FCOM, the max angle for the nosewheel of the 340 is 65°.
Actually we have had a lot of technical notes about it since the gear collapse of one of our 340 a few years ago, and some changes were made to the software as well. So I am not 100% sure about it.
On newer models it is probably different.
On our newest 330 the max angle was 72°.

Greetings.
 
Mr.BA
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RE: Some Questions On The B767 And A340

Sat Apr 27, 2002 7:44 am

Thanks again Rick Skystar and FLYSAB. Very interesting I thought.  Smile No worries Rick I'm sure everything will be over soon so just bear with it  Smile I'm sure you wuld like your new house! But I would sure want to know what's so worrynig about me dreaming over the B767! Big grin How's life in AUS Justin?

Do you guys have these figures for the B767/A340? The B744 has:

- 2000 feet above optimum altitude, 1-2% increase in trip fuel.

-4000 feet below optimum altidute, 2-4% increase in trip fuel.

-8000 feet below optimum, 8-12% increase in trip fuel

Cruise M.01 above schedule, 2% increase in trip fuel

Thanks all again! Cheerios!

alvin
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Mr.BA
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RE: Some Questions On The B767 And A340

Sat Apr 27, 2002 9:33 am

The "-" was meant as a bullet point not "minus". Sorry!
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GE
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RE: Some Questions On The B767 And A340

Sat Apr 27, 2002 10:19 am

For B767,
if I recall correctly,
2000 FT above optimum – 3 percent increase in fuel usage
4000 FT below optimum – 5 percent increase in fuel usage
8000 FT below optimum –12 percent increase in fuel usage
M.01 above M.80 – 3 percent increase in fuel usage
 
Rick767
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RE: Some Questions On The B767 And A340

Sat Apr 27, 2002 5:56 pm

Not so sure on this one...

Our Flight Training Manual for the 757/767 gives the following figures:

2,000ft above optimum = 0.5% - 1% fuel penalty
4,000ft below optimum = 1% - 3% fuel penalty
8,000ft below optimum = 2% - 5% fuel penalty
Cruise Speed 0.01M above schedule = 1% - 2% fuel penalty

The table does not specify, however, whether it is specific to the 757/762/763. I would presume the figures differ quite a bit for each variant. I have a feeling the ones above actually refer to the 757. Don't have a performance manual myself so couldn't check for sure.

If you look at the 767-300 Cruise Tables though, the figures GE states above look more realistic.

For example, an increase in cruise speed from Mach from 0.80 to 0.82 over an entire flight results in roughly a 3% increase in fuel burn, but then the increase between 0.82 and 0.84 results in a 9 - 10% increase!
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tsentsan
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RE: Some Questions On The B767 And A340

Sat Apr 27, 2002 7:42 pm

Hi Rick767, FlySAB, GE, Justin and Alvin,

On the subject of steering I've got a few quick Q. I've kinda heard that tillers are not really used *all* that often unless in a tight situation. I mean I've heard that rudders pedals are used more often in steering the aircraft for normal taxying. Would this be an accurate statement?

Also on the 767 and 340, can the main gears tilt horizontally to aid in the steering functionality (sort of like a cars' 4WS) ? Wouldnt the 345/6 need additional steering capability with it being the longest aircraft in the world?

Thanks guys. Of course, happy advanced birthday to Justin.

Signout,
Tsentsan
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GE
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RE: Some Questions On The B767 And A340

Sat Apr 27, 2002 8:19 pm

Hi Tsentsan,
Tillers are used for steering on taxiways or when lining up on the runway before takeoff. The tiller is very sensitive and allows about 70degrees nosewheel steering but the rudder only gives 7-10degrees.
So the rudder would not really be effective for normal steering but it is used during take-off as at high speeds, using the tiller would most likely cause overcorrection. A small movement on the tiller would likely cause a large direction change on the nose wheel.

As for the main gear tilting horizontally, are you referring to main gear steering? If so, I think only the 747 has this feature.
I don't know about the A340-500/600 though.


Regards,
Russell J.
 
tsentsan
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RE: Some Questions On The B767 And A340

Sun Apr 28, 2002 2:55 am

Russell,

Thank u, has cleared up my doubt on that issue  Smile/happy/getting dizzy
I think the 777-300 has the main gear tilting/steering feature too cos its wayyyyy too long...  Smile/happy/getting dizzy... So thats why I asked whether the A345/6 would have it too.

Thanks  Smile/happy/getting dizzy
Tsentsan
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Mr.BA
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RE: Some Questions On The B767 And A340

Mon Apr 29, 2002 3:55 pm

Thanks everyone for the responses again.  Smile Just wondering if the ETA at destination given by the FMC takes descend into consideration? If not, wouldn't you arrive 10 or 15 minutes later than the ETA time given by the FMC?

Thanks.

alvin
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Rick767
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RE: Some Questions On The B767 And A340

Mon Apr 29, 2002 5:30 pm

Alvin,

The FMC models the descent quite accurately, and based on entered speed and altitude restrictions across the descent profile via a STAR to the expected landing runway, will generate a very accurate time and fuel prediction for landing.

The ETA is also constantly updated. So if a new arrival routing or runway is given by ATC once that information has been entered into the FMC the ETA will be immediately updated.
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tsentsan
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RE: Some Questions On The B767 And A340

Tue Apr 30, 2002 2:31 pm

Rick767,

Got a Q regarding ETA ... lets say you're assigned XYZ STAR, but whilst on descent, you're told to cancel the STAR and given radar vectors? Would you modify it in the FMC or just use HDG hold and fly it down?

Thanks
Tsentsan
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Rick767
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RE: Some Questions On The B767 And A340

Wed May 01, 2002 7:07 pm

Tsentsan,

First of all we would use Heading Select when given radar vectors, Heading Hold on the 757 / 767 (and as I understand most Boeings) merely holds the aircraft’s present heading and rotating the heading knob to whatever value you like will have no effect on this, the a/c will continue to hold it’s present heading. So with heading select we push the heading knob and can rotate it to command a new aircraft heading.

To the question though! It really depends where we are, what we have been told to expect by ATC or what we think is the most likely routing from the present point. Once we are given a radar vector by ATC, we must use heading select as dictated by our SOPs. If we are told to cancel the STAR that would imply to me that our continued path will be based on radar vectors only, and will probably not resemble the STAR route. More importantly, it suggests that we will not be asked to pick up the STAR routing again at any point nor will we be asked to proceed to any waypoint on the STAR route. Once we are in heading select mode we would therefore ask the FMC to delete the STAR waypoints, and make the next waypoint the Centre Fix for the arrival runway, or whatever sensible programmed waypoint we choose.

For example coming into Orlando from the north for Runway 18R we may be asked to “fly heading 240”. In this case we would just go ahead and do that, but keep the STAR in as we may be asked to resume our own navigation at any time. A good example of this is weather avoidance or conflicting traffic. If we were told “fly heading 240, radar vectors for the ILS” we would go into heading select, but then make the next waypoint the centre fix or the ORL VOR or at some airports just put an intercept leg to the runway centreline. This is because by telling us we are now having radar vectors to the ILS, the controller is unlikely in a normal situation to ask use to resume our own navigation via the arrival route.

Hope this made some sense, there are so many different scenarios it is hard to have a set rule on this one!
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tsentsan
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RE: Some Questions On The B767 And A340

Fri May 03, 2002 2:55 pm

Rick767,

Roger that, thank u  Smile/happy/getting dizzy Makes it simplier now.
What if ATC doesnt tell u to cancel STAR, mainly somethinglike "Fly heading 240 for seperation, xxx miles to touchdown".. Would you still remove the STAR coordinates from the FMC?

Another Q is that, assume you're told to go on radar vectors but ATC doesnt tell you to cancel the STAR. By then, you're on the ILS. Would you then remove the STAR waypoints from the FMC, or would it be way too busy on the ILS than the monitor the FMC?


Also 1 more event, when I came back to Perth, we had a Vapp of 138, and a Vref of 133. When I went up the deck after landing, the Speed bug was fixed at 138. How would the PF slow the a/c down so that it touches down at 133 instead of 138. I realise they cut thrust and flare at 50 feet, but would this thrust reduction be enough to slow it down 5 kts? If the PF flared too early, would his Vref be lower? Also, does the FMC show the Vref or the Vapp or both?

Thanks, and sorry for the many Questions...

Tsentsan
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Skystar
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RE: Some Questions On The B767 And A340

Fri May 03, 2002 6:14 pm

You can lose quite a few knots in the flare.

I would even bet that the aircraft touched down below Vref.

Cheers,

Justin
 
Rick767
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RE: Some Questions On The B767 And A340

Fri May 03, 2002 7:43 pm

What if ATC doesnt tell u to cancel STAR, mainly somethinglike "Fly heading 240 for seperation, xxx miles to touchdown".. Would you still remove the STAR coordinates from the FMC?

This is one of those cases when it really would just depend… primarily where you are on the STAR for a start, and how much the radar heading given by ATC differs from the arrival route. If this instruction was issued I would imagine the controller would continue to provide vectors to the approach, or a later fix, so some sensible fixes on the STAR could be removed or we can leave them in until we are sure. Of course, we can always ask ATC what their intentions are - after all they are there to help us. It isn’t very often ATC leave us second-guessing and if they ever do I always ask.

Another Q is that, assume you're told to go on radar vectors but ATC doesnt tell you to cancel the STAR. By then, you're on the ILS. Would you then remove the STAR waypoints from the FMC, or would it be way too busy on the ILS than the monitor the FMC?

We would have removed them before reaching this point, or the FMC would have removed them itself provided our route was close enough past each waypoint. By that stage of the approach as you say even with two people on the flightdeck the last thing we want to be doing is reprogramming the FMC, so under normal circumstances a good airman will have setup the FMC in advance (probably a centre fix-to-runway arrangement or an intercept course to the runway).

the Speed bug was fixed at 138. How would the PF slow the a/c down so that it touches down at 133 instead of 138. I realise they cut thrust and flare at 50 feet, but would this thrust reduction be enough to slow it down 5 kts? If the PF flared too early, would his Vref be lower? Also, does the FMC show the Vref or the Vapp or both?

The FMC shows only Vref, we calculate the Vapp ourselves based on wind component and gust factor (if there is none of either at the surface Vref + 5 is Vapp, but it can be as high as Vref + 15). Following the proper landing procedure the thrust reduction is easily sufficient to remove this small excess speed. In fact as Skystar correctly says, the actual touchdown speed will often be lower than Vref, there is no problem with this, as long as we’re not already below Vref at 150 feet or anything!

(p.s. I note the topic now has 5 stars! Well done everyone who took the time to answer the tech questions, even if we did stray a little “off-topic”!)

Rick.
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Mr.BA
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RE: Some Questions On The B767 And A340

Fri May 03, 2002 9:21 pm

Thanks everyone for keeping this thread alive! Really learned much more about the A340 and the B767! Cheers to all!

Just thought of another question. Is there a function on the thrust levers on the A340/B767/B747.. etc that can be tuned or adjusted to minimise thrust levers activity during cruise especially in turbulence and in strong gusty winds?

Thanks!

alvin
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Rick767
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RE: Some Questions On The B767 And A340

Sat May 04, 2002 1:33 am

Alvin,

No, there is no such "damping" tool on the 767 throttles. Our company recommends use of the autothrottle system as much as possible, stating that it is "well-developed for maintaining speed even in gusty and turbulent conditions", though kind of contradicts itself later stating that it "may be better" to use manual thrust for accurate speed control on approach in gusty conditions!

But generally it works pretty well, so I think Boeing "built-in" a kind of damping facility for these situations.
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Mr.BA
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RE: Some Questions On The B767 And A340

Sun May 05, 2002 8:33 am

Thanks Rick767 once again.  Smile



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Mr.BA
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RE: Some Questions On The B767 And A340

Mon May 06, 2002 7:35 am

Anyone can help me with this? What's the average climb rate of the B767 after taken off at MTOW passing FL 280 for FL 310? I suppose you would be climbing at 313 knots or so?

Cheers

alvin
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tsentsan
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RE: Some Questions On The B767 And A340

Mon May 06, 2002 5:28 pm

Rick,

Thanks mate  Smile/happy/getting dizzy Sorry didnt reply earlier been busy with assignments.. :-(

Hehehe,,, see ya around
Tsentsan
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Skystar
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RE: Some Questions On The B767 And A340

Mon May 06, 2002 8:42 pm

Alvin,

You sound like you're having a bit of fun with Flight Simulator  Smile

Cheers,

Justin
 
Alberto Riva
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RE: Some Questions On The B767 And A340

Tue May 07, 2002 9:04 am

Small correction on the 767-200 MTOW: the highest is actually 175 540 kg (ER operated by South African and Air Zimbabwe with PW4056).
 
Mr.BA
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RE: Some Questions On The B767 And A340

Tue May 07, 2002 3:51 pm

Yeah I am Justin...  Smile Using the PSS panel on the B744... certainly the best panel I have ever used.  Smile
Boeing747 万岁!
 
Rick767
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RE: Some Questions On The B767 And A340

Tue May 07, 2002 6:07 pm

Alvin,

With regard to climb rates, from my own experience and memory!!

763 Takeoff at about 175t (10t off MTOW) for a flight to MCO typically, lowest ROC we see is about 1,200 ft/min through FL280-300 (where the speed-to-mach transition takes place).

On a heavier flight (say Cancun, near enough MTOW) it may be down to about 1,000 fpm at that point. The ROC itself will increase just after that altitude as the aircraft begins to climb in MACH so IAS is reducing in the climb not constant as before and speed drives pitch attitude = ROC. Hope that made sense?!

But yes it is rare to see less than 1,200 fpm at any stage of the climb on the 763 even when heavy, climbing to "normal" flight levels (2,000 above optimum or thereabouts).

Rick.
I used to love the smell of Jet-A in the morning...

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