Vorsicht

I'm guessing you've never flown a 707

V

atiuta

Why stay in the dark ages if you don't need to.....

trimotor

The use of V/S in the climb is entirely valid, though its only practical application is ROD reduction for TCAS considerations approaching intermediate level-off's and TOC points that are below the MAX in the 300ER. ROC will often be 2500 fpm+ at this point, especially above FL310ish, when it's switched to mach no climb schedule.

Wiley

You are quite correct. Vorischt. I was alluding to the era if that's any excuse.

NO LAND 3

V/S is just a pain for making a level change. No less than four separate actions involved plus you must remember to set the new cruise level in the FMC. And don't forget to reselect VNAV you rascal! How about flying the plane as the manufacturer designed it. It is obvious whether a conflict is likely if you look at the TCAS display; in which case v/s may be appropriate.
I was under the impression that TCAS 7.0 reduced the likelihood of inappropriate TCAS RAs as well.
Life can be so simple...

typhoonpilot

Apparently not as much as thought. Here is an excerpt from the most recent TCAS Safety Bulletin

"The Aeronautical Information Manual, 4-4-9 (d) says “…Descend or climb at an optimum rate consistent with the operating characteristics of the aircraft to 1000 feet above or below the assigned altitude, and then attempt to descend or climb at a rate of between 500 and 1500 fpm until the assigned altitude is reached.” Similar guidance is found in the FAA’s AC120-55B, “Air
Carrier Operational Approval and Use of TCAS II.” Modern Flight Management Systems (FMS) designed for optimum efficiency do not comply with these guidelines. EUROCONTROL has published ACAS II Safety Bulletins that make similar recommendations.

Many TCAS operational experts believe that at a minimum, crews should follow this procedure when they are aware of conflicting traffic either by advice from Air Traffic Control, information from the TCAS traffic display, or by having received a TCAS Traffic Advisory. The International Civil Aviation Organization (ICAO) has had discussions on this issue since 2000. As a result of these discussions, the seventh meeting of the Operations Panel, held in May 2006, agreed to recommend the following amendment to International Standards and Practices (PANS-OPS):

When the pilot is made aware of an aircraft at an adjacent altitude or flight level by an airborne traffic display, the pilot should consider using appropriate procedures to ensure that a rate of climb or descent of less than 8 m/sec (1500 ft/min) is achieved at least 300m (1000 ft) before the assigned level.
An additional recommendation proposed by the Operations Panel requires operators to specify the procedures for compliance.

Concern has been expressed about crews flying highly automated aircraft
interfering with aircraft automation. TCAS monitoring programs show that reducing the vertical speed nearing level off altitude, especially when the crew is aware that there is another aircraft in close proximity at an adjacent altitude, greatly reduces the probability of an aircraft receiving any RA.
Limited surveys of airline crews show that most airlines do not teach this procedure. However many crews have adopted this technique and are comfortable employing it. Many unnecessary TCAS II advisories are generated when aircraft approach their cleared level-off altitude with a high vertical rate when another aircraft is in close vertical proximity. A recent
study has concluded that reducing vertical speed during the last 1000 feet of a climb or descent to 1500fpm or less may reduce RAs in European airspace by at least 22%, and the number of “nuisance” RAs by at least 43%. Data collected by Lufthansa demonstrates that crews who reduce their vertical speed when approaching an assigned altitude realize a 67% reduction in the
number of RAs received when compared to those crews that do not reduce their vertical speed"

Linky to the full article.


Typhoonpilot

atiuta

I don't think anyone is disputing the value of V/S if a TCAS situation is likely.

I fail to understand however the desire to use V/S in the latter stages of a normal climb and there were some posts earlier disparging the mode in the terminal area on descent.

V/S is there for a reason, not every reason. Like any mode it has a time and place. TOC, full thrust, subtle speed decay is not one of them.

NO LAND 3

[QUOTE=typhoonpilot;3034963].
crews should follow this procedure when they are aware of conflicting traffic

Thanks for an informative post TP. I'd like to make a training point: I find the trainers tend to advocate use of v/s for any FL change in RVSM airspace (ie 95% of our ops) when in fact there is no point if no obvious conflict exists. I prefer to leave VNAV engaged in this case.

readytocopy

No one is saying that the standards should be relaxed after being hired....are we doing what we do because it is good airmanship or are we just doing it because it is in the FOM and we are covering our butts. This has nothing to do with standard...Airmanship is GONE....by the way Homer...I have a few more....I don't want to be briefed about the cost index and the wind component...or a particular taxiway that is closed on the other side of the field....don't tell me about the mountains by Fujerah....oh by the way if we had a emergency descent...I am not going to pull out the DARD...I am going to use my EGPWS and grid MORA and my eyes and get an idea of the altitude I am going to descend too. It is funny we use EGPWS to avoid CFIT but it says in the FOM not to use it a method of navigation....Why are these methods so frowned upon and thought of as unorthodox when I look at it as making a complicated situation into a simple one by using the tools provided....oh and "damn if you do and damn if you don't"...there is no winning. I personally think we are so scared of our own shaddow that something is going to happen.

violate

Its simple, EK policies are produced with one primary goal, to protect the company in the event of pilot error. They are NOT produced to support you to do a better job

777SandMan

Pitty that these individuals do not read these forums and stay in touch with what is happening in their kingdoms! As it is prime holiday season, they are most likely lazing away around a pool / ski slope / beach. (Delete if required).

Marcellus Wallace

TCAS Change 7.0 or ACAS II was introduced for RVSM - you no longer get "TRAFFIC TRAFFIC" flying past another with 1000 feet separation - the envelope was changed to the region of 700-800 feet.

Plus when 2 aircraft converge - one climbing and another descending the logic in the software would be inclined to give you commands which required the least v/s change i.e. climbing/descending through each others levels - TCAS is not coupled and does not know what the Autopilot is doing i.e. ALT ACQ/ALT *

Good idea to reduce the ROC/ROD approaching cleared levels/altitudes by whatever means.