Pilot Pete's Performance

[chillie]

In response to pilot petes excellent post on "expedite" .

I am thinking about developing a short course on performance to assist our blip-drivers (simulator pilots).

Would pilots like to fill in or change the following form to give some different ideas as to what they would like with regard to Approach. (bearing in mind that ATC requirements might be different) Company requirements would also be useful. Ideal figures for CDA etc.

ACFT Type: Operating Co:

Descent from FL 240 to FL 100.

Ideal…. IAS: ROD:
Acceptable… IAS: ROD:

Notes…..


Descent from FL 100 to base 15 – 20 NM.

Ideal…. IAS: ROD:
Acceptable… IAS: ROD:

Notes…..

Base to 10NM.

Ideal…. IAS: ROD:
Acceptable… IAS: ROD:

Notes…..

10NM to 4 – 5 NM.

Ideal…. IAS:
Acceptable… IAS:

Notes…..

Final Approach

Ideal…. IAS:
Acceptable… IAS:

Notes…..

[Dances with Boffins]

Good luck with this mate. We've been trying to get the two-winged master-race to impart their performance figures to us at NATS for years. We have got some "look at the radar and guess" figures in our simulators, which we use for ATC training and airspace design, but it would be much better if we knew exactly what ROC a Ryanair 738 wanted out of Manchester etc so that we could train to give exactly what the "customers" want, rather than have them whinging at us all the time about us not giving them their optimum profile.
The performance models we use are state of the art, but are only as good as the figures that are put into them. So come on chaps. Get the books out and deluge the boy with all the descent rates and IAS figures he needs. Then we'll do climbs...

[BOAC]

Chillie - several threads back as far as 2001 where we have tried to thrash out common vectoring/final speeds.

http://www.pprune.org/forums/showthread.php?t=3437 where post #66 seemed to be a reasonable compromise.

We also had http://www.pprune.org/forums/showthr...threadid=15896 and http://www.pprune.org/forums/showthread.php?t=123594.

These may be a start for you?

[Max Angle]

We've been trying to get the two-winged master-race to impart their performance figures to us at NATS for years.

And with an attitude like that it's unlikely any will be forthcoming.

[chillie]

Max Angle, I think you missed the smiley face

After people seemed so happy with "pilot pete's" post on 'expedite ', I thought there would be other people who would be happy to get some real figures.

At least we tried....

[Pilot Pete]

but it would be much better if we knew exactly what ROC a Ryanair 738 wanted out of Manchester etc

I think you may misunderstand what pilots want. We don't want a rate of climb, we want to fly our ECON (economy) profile in VNAV, unrestricted all the way up to cruise level. That is our ideal profile for economy and comfort.

This results in a varying rate of climb throughout the profile. The higher we get the less the rate becomes as we run out of puff (that's a layman's terms) until we just about make it to our ideal cruise level!

So, from take-off we climb fairly steeply until we reach flap retraction altitude, then we reduce our rate of climb and accelerate to clean speed. We then tend to keep accelerating (depending on terrain etc) to 250kts. Once at 250kts we then raise the nose to keep that speed and thus our ROC increases again. If we are released from speed control, or failing that as we pass 10,000ft, we again lower the nose (and hence ROC) to accelerate again, this time to our ECON climb speed, which we want to hold all the way up to our ECON cruise level.

Many, many factors will affect what ROC we achieve during this whole process, from temperature to headwind/ tailwind, a/c weight, MEL restrictions etc etc.

So we don't have a ROC that we could ask you for that would be ideal.

Hope this helps.

PP

ps. relieved to find out what the subject of the thread referred to! I was getting a little worried.

[Spitoon]

We don't want a rate of climb, we want to fly our ECON (economy) profile in VNAV, unrestricted all the way up to cruise level.

And anyone with a bit of experience and an interest of how the flight deck side of the business works would understand this sort of thing.

[Mister Geezer]

Sounds like a good example of why we should be encouraging fam flights (providing your company allows it - mine does).

[BaldEd]

Thank you Pilot Pete for a most interesting explanation on modern aircraft climb performance needs. I'll be endeavouring to follow that in my Sim Pilot duties.

[GetTheFlick]

I think you may misunderstand what pilots want.

I always thought they wanted to be treated like the only airplane in the sky.

(Sorry...I couldn't help myself)

Don Brown
Atlanta Center - Retired

[chillie]

PP

Thanks for that. We appreciate your posts.

Whats is of more interest is what you would like, and can accept on descent and approach.

With most busy units pilots are not going to get their ideal. (only acft in the sky stuff ) Not until the system changes anyway.

[TheKabaka]

ACFT Type:A319,A320,A321 Operating Co:BA

Descent from FL 240 to FL 100.

Ideal…. IAS300-320 kts: ROD:A/R a rough guide would be 5* the ground speed(more if high lss if low on the profile which we calculate as 3* distance to landing
Acceptable… IASmin clean to max (220-320ish kts): ROD: very wide range here, 6000 ft/min is poss esp for a short time
Notes…..


Descent from FL 100 to base 15 – 20 NM.

Ideal…. IAS:would generally like to keep speed up here say 300, but need to start slowing down at LEAST with 15 miles to go ROD: A/R
Acceptable… IASWe can slow to final App speed if required as low as 125 kts, and up to 300 kts: ROD:A/R

Notes…..wrt to ROD the notes about distance to go and ROD alwyas apply when calculating our progress relative to the ideal 3 degree profile

Base to 10NM.

Ideal…. IAS:180-210kts ROD:maintiaining the glide (5*GS)
Acceptable… IASVapp to 210: ROD:maintain glide

Notes…..

10NM to 4 – 5 NM.

Ideal…. IAS: 160 kts
Acceptable… IAS: unable to keep any more than 160 really

Notes…..

Final Approach

Ideal…. IAS:at 4 miles have to reduce speed to achieve stable app
Acceptable… IAS:Vapp min

Notes….. Wind plays a major factor, a tailwind will reduce all these speeds as a higher GS means we have to have a higher VS to stay on the profile (5*GS remember). A healthy headwind will help us altough I doubt most pilots would increace the maximums I put above. Also as often said to us on these pages by ATC, why not ask us? then everybody is on the same page

[MANAGP]

Almost impossible to anwer with Cost Indices changing on a near daily basis!