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Seat of Pants Performance?

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Seat of Pants Performance?

Old 16th Feb 2015, 20:47
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Seat of Pants Performance?

Flying a medium/large Biz Jet (Legacy) on a freelance basis for a private world wide operation, I'm amazed that the other crew don't bother to evaluate performance even though APG is available to us. Perf limited (mainly departure) in all sorts of places; but One Engine Inop Departure Procedures and related performance are available at the press of a button. Me - check every time. Others never bother. Why such indifference? One quote - "well perf t/o limit (Aspen) is only in case one engine fails....so it doesn't matter if we are a couple of tons overweight."
"Olbia - just fly out visually".

What do you think? I'm covered because I stick with published figures and applicable OEI Departure Procedures (DP), but (having a previous life in airline world) I am appalled by what I consider lack of professionalism by my colleagues. Often not even consideration of DP. Hard work convincing the FO that I am not over reacting.
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Old 16th Feb 2015, 21:26
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Please don't even get me started on the idiots that fly some corporate jets.

Way too many of them load up their aircraft to meet the minimum 2.4 degree climb gradient with the excuse it is "VFR" even in places like Aspen or Vail just to name a few.

Their 2.4 climb gradient is only going to get them to hit a rising terrain usually CG (cumulo granite) and the best part is they are going to see it happening!

Then there are those that go a step further by not even bothering whether it is VFR or IFR, they just load up to make the mission work and none of them bother to check their single engine performance when icing conditions prevail.

Too many amateurs are flying around.

Last edited by Jet Jockey A4; 18th Feb 2015 at 14:21.
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Old 17th Feb 2015, 01:01
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In this thread:

http://www.pprune.org/biz-jets-ag-fl...jet-types.html

Anyone expressing caution or suggesting that safety margins exist for a reason was shouted down by three or four pilots with apparently astonishing skills that saw nothing wrong with condeming those that favoured a less gung-ho approach.

That being so - I'm surprised that you are surprised. This business attracts Alpha types. If they are not unlucky enough to die in early ops they can, unchecked, end up in a situation where they tell people like you and I what to do.

A mate of mine used to tell me: "maintain standards Jon, because in this business there's no one checking to ensure you do."

It's great advice and as far as possible - when I've found myself working for one for the aforementioned bellends I've bailed out as soon as practical.

Life is short, and dying because some c*nt thinks performance factors are for pussies is not part of my game plan.

Last edited by JonDyer; 17th Feb 2015 at 01:45.
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Old 17th Feb 2015, 05:06
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Aspen,Samedan,Jacksonhole, Graz,Innsbruck all these airports are special airports, with special procedures, departing or landing. To these procedures are "attached" a maximum weight to operate from. Providers like Flygprestanda or Jeppesen are offering this golden number of MTOM for the conditions of the day.

America is peculiar because of TERPS criterion for procedure design which is completely different from the PAN-OPS 4 design. ( it is closer to PAN-OPS 2)

As a consequence, a lot of pilots are used to the 48ft / Nm 0.8% percent of clearance on departure, and were taught that way 20+ years ago; and JohnDyer you are right; you have to maintain a standard, because in many small outfits, nobody will do it for you.

The real issue here, especially in private Ops, is what is the boss accustomed to ? If being flown by people whom are disregarding the numbers, because engine never fails in real life, just in the simulator, it will be difficult to tell him suddenly that he can only fly by himself or fuel stop, or leave all these bags behind or a combination thereof, just because of a captain change. But like it is written here, you will find someone, always, that would load to the ceiling, fill the tanks, and go.
Airlines are a bit firewall to this ( but again, airline pilots have to trust the load sheet done by someone else, after all they did not weight these pallets), but they have other challenges.

The best piece of advice ( funny one) came from John and Martha King :

" And remember : Stay out of the Trees ! "
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Old 17th Feb 2015, 05:19
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No jet experience, no turboprop, but I learned flying light twins out west that "you can't wish the fuel back into the truck".
Pilots flying with me would ask why I did not fill up, we were below gross weight, you filled it on the flatlands, etc.
I told them I wanted the chance to make it back to the numbers, nothing more. No more fuel than I needed to get to the next stop. The next stop may be a little closer for a mid day summer departure
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Old 17th Feb 2015, 06:00
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Ignore the numbers at your peril, you can't beat physics!

When my number comes up, I want everything going for me that I can!
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Old 17th Feb 2015, 17:47
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Jackdaw,

I couldn't agree more. You should check the figures and use APG. If the FO thinks you're over-reacting the good CRM means you should brief him on what you consider important as Commander, and more importantly, why! I always check the figures (Part 91 - private), and always have done.

JonDyer, of course, that thread was on a slightly different topic to this one. Please don't muddy the waters. Comments there were regarding following the book figures and getting the performance stated. I feel this thread reflects that, and has my full support. As for shooting people down, there is quite clearly a feeling that comments needed to be justified, other than lets "just add it on" and therefore think we are safe because we have done that. If you wish to be involved in the thread, then get involved and try to educate others.

JD, I must say your comments regarding "maintaining standards" are spot on.

CL300 - sensible as ever.

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"May common sense prevail"
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Old 18th Feb 2015, 12:54
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muddy waters! thats going to be Jons new nickname..

Just so I'm clear, what if I go and plan an arrival and subsequent departure that all performance calculations say I can do but only just.. Am I gung ho? or is that ok? Because Guru or AGP or whoever you want to use will only tell you if you can do it or no. They don't tell you by how much. You will get a weight limit and thats it - and if the weights ok do we just lob off without any further consideration?

I'm sitting here right now considering the viability of a Global Express into a 4200' airport with climb performance issues because of terrain and temp and I am doing it with both Guru and the AFM because Guru says I can and I want to know by how much. Does it make me gung ho because I'm considering it?

thats a genuine question by the way. I have the feeling that its no longer acceptable to use a manufacturers performance figures for an aircraft - you have to use a fudge factor too...

I might adopt the username gung-ho on here. quite like it.
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Old 18th Feb 2015, 12:55
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Jack, Jon & Jet,

Speaking for my sector of our industry, I hope that these rude and rather arrogant comments are not directed at the thousands of competent, professional crew who work in business/corporate aviation public transport operations?
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Old 18th Feb 2015, 13:20
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@ the Wings...

I hope that these rude and rather arrogant comments are not directed at the thousands of competent
No at least my comment was certainly not directed to the more professional corporate pilots.

This said I have seen more pilots leaving Eagle and Aspen and other critical airports with absolutely no plan of action and way overload in fuel just to "make it convenient" for the boss. Why stop in Denver? Let’s make it direct and who cares about single engine performance. There are a lot of corporate pilots out there that have that attitude.

BTW, another area where I am highly critical about with some corporate pilots and I see all the time is the deicing and ant icing dilemma. Too many pilots to save money for the operation or to save time will not deice or anti ice their aircrafts prior to departure.

Anyway sorry if I offended you that was not my intent.
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Old 18th Feb 2015, 13:40
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@ tommoutrie...

Your question is very valid...

I do not believe the aircraft manufacturers are lying about their performance data but they sure make it very hard to go through the charts and get a figure without making a mistake.

When you buy any aircraft today, you ought to be able to with some sort of software to get the "correct/approved" AFM numbers.

This "software", an electronic version of the approved AFM performance chapter should be given to the operator as part of the purchase of the aircraft.

Now even if you come up with the "correct" numbers it is in no way giving you the appropriate airport analysis so you still need to go to an outside source for that like APG.

APG or any other supplier of airport analysis will come up with numbers that meet the minimum standard to clear an obstacle in their procedure and yes those are very small margins.

It is up to you to decide if you want to get the most out of the analysis or back off a notch and use a safer number (higher OAT or less weight) to give you an additional buffer.

The airlines to it the same way, there is no magic in their procedures. I have seen American Airlines leave people and baggage behind at Eagle for flights to Chicago and this with a B757.

FYI, in Eagle our ops with the CL604 for takeoff was day basically VFR (5000' - 3 miles) and load up the aircraft (pax and fuel) to meet the climb gradient required to clear the obstacles for a given OAT.

Note: You could not factor in engine or engine and wing anti icing into the numbers unless you planned to stop in Denver.

For landing, especially at night, if you did not see the airport while on the LOC at 10 miles final you were not to land there, no circling is permitted.
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Old 18th Feb 2015, 13:56
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oh I understand now. The

"Please don't even get me started on the idiots that fly some corporate jets"

which is right up there with

"some of my best friends are black"

was applied to corporate pilots like me who are spending the afternoon working out whether an arrival and departure are possible from Santos-Dumont using Guru and the AFM in order to ensure I have accelerate stop, accelerate fail go, 115% go, close in obstacle climb performance OEI, distant obstacle clearance OEI etc but you're the one who departs on an IFR plan with his plane too heavy to comply with an IFR gradient if you switch on the wing and engine anti ice?

yup, totally get how unprofessional I am now.. sod it, I won't bother, its a nice day and I'm by Copacobana beach, I'll go and look at some bottoms instead and wing it tomorrow..
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Old 18th Feb 2015, 14:13
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Jackdaw

What performance calculations did you do in your former life as an airline pilot? Or did someone else do it for you and you just read the bit of paper with an emergency turn procedure and banged it all into the FMS? When is the last time you sat there with the AFM and actually plotted obstacles and worked out the gradients OEI. I have an excel file that I sometimes use to plot obstacles in order that I can wind adjust a required climb performance gradient - something that airlines never do and nor to APG or Guru or anyone else I know - because I want to understand how the 1000' tailwind I'm about to fly into is going to affect my climb gradient? You don't have to be reliant on these programs to magically tell you if you can make it - I've been working on what we can do out of Cuzco and I wouldn't actually take as much fuel as Guru says I can because I am concerned that in the event of an engine failure at V1 my climb gradient would be significantly degraded by the 30kt katabatic that you are likely to encounter and that the associated turbulence that I would expect may degrade my own ability to fly the profile should a failure occur. So instead of just using Guru and putting as much fuel in as it say I can I have factored these things in and set an appropriate limit. Equally, on a nice day, if I've got a 4200 foot LDA runway, and my LDR is 4100, and I'm fully servicable, and its where the owner wants to go, why wouldn't I land there? Isn't that what being a corporate pilot is all about? That and the drinking and the girls?
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Old 18th Feb 2015, 14:14
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flight delayed/cancelled...

I am actually going to the beach

out
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Old 18th Feb 2015, 14:19
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@ tommoutrie...

OK so now I'm a racist too! WOW!

"Please don't even get me started on the idiots that fly some corporate jets"
I don't know what your problem is but even in your quote of my phrase you can see that I mention "some" and to me that means not all corporate pilots are idiots.

Perhaps the way I worded it was incorrect, so again I'm sorry for the inconvenience.

Anyway carry on, I'm not going to get into a pissing contest with you.

Last edited by Jet Jockey A4; 18th Feb 2015 at 14:33.
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Old 18th Feb 2015, 14:43
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no you're not necessarily racist - it was a parallel I used to demonstrate how stupid your original comment was. You recognised that

"SOME of my best friends are black" is likely to have a racist connotation because it is usually said in conjunction with the defense of a racist standpoint.

by saying

"Please don't even get me started on the idiots that fly some corporate jets"

you are similarly maligning the career of thousands of corporate pilots. I don't recognise the corporate type you and Jackdaw are talking about. Admittedly, I don't know all that many corporate pilots but the ones I know take their jobs very seriously. I don't know any at all that are happy to poach a bleeds off packs off hooky departure to just about comply with a VMC net climb gradient of "miss the hills"

well I may have just met one.... who oddly enough is chucking rocks at the rest of us..

oh my god there's not a lot of material required to make that bikini..

Last edited by tommoutrie; 18th Feb 2015 at 14:44. Reason: I can't spell
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Old 18th Feb 2015, 15:57
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margins : How much.

PAN-OPS 4 LAND : up to MSA-1000ft or 25 km : gives you with the infamous formula of 60m + half the wingspan+ 0.125xd a clearance of 35 ft Straight and level or 50 ft in the turns. up to EFRA at V2+10 max 5minutes T/O power. After that, you do not know where you are for sure, but it is your turn then from out of the blue.. ( Where is the area chart ? ;-) )

TERPS LAND : 48 ft per NM = 0.8% if no indication clean at 400ft AGL ends at MEA-500ft or grid-mora if no valid data available.

This is of course if no EFP are depicted, GVA springs to mind because it is a classic example, and everybody goes there on RWY 23...

PAN-OPS 2...Same as PAN-OPS 4 EXCEPT that acceleration is set at 820 ft if no other information is given.

One can understand why most of OMB are set to CS25 with the minimum altitudes at 1000/1500, no brainer , cover most of cases, the other ones are very likely to be special airports with special training anyway ( Lowi, EGLC, KJAC, etc.)

Now the weight that you get and the trajectory associated is of course that Maximum All up weight that you can carry on that day; your knowledge of the airport and the surroundings ( the thing called experience, but that nobody wants to pay for) may make you choose anything below that weight, but certainly not above, and sometimes, for some people it is like an awakening : WHAT ? I can only go with 2 hours of fuel ?? These data is BS, i normally go full fuel out of here... Sorry bob...

You have to draw a line somewhere, and in the very changing world of business aviation, i would rather have pilots looking at one line and one number than to go long hand in the performance book under time pressure, but this is me...

Anyway Experience and CRM prevails when operating on the edges of the envelope , Max gross on a F2TH Easy at 50°C even at sea level in DXB is interesting on two engines, on one it is certification gradients.....

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Old 18th Feb 2015, 16:24
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@ CL300...

Thank you!

He is over complicating the whole process. In fact he is the opposite of the ones that don't even bother with trying to figure out some sort of safe departure.

Unfortunately you have to go with what's available and that I'm afraid it is not much when it comes to safety factors in cases like this.

The way he goes on to "rant" about his flight to XXXX airport is pathetic. I think he should go to the beach and get hammered.

Oh yes, perhaps I should also in my calculations, take into consideration a possible tail wind on departure, perhaps an inversion while at it too... Where do you stop?

The truth is you might as well stay home and not fly at this point. No company I know off can simulate all kinds of scenarios for your departure.

Company SOPs help too. What is the minimum RWY length for a Global Express as stipulated in your company SOP? Maybe your company does not use SOPs which sadly I have seen too often in the corporate world. BTW, our minimum RWY allowed is 4500' dry only.

It's really simple... You don't feel comfortable going into a 4200 foot RWY, don't go! Leaving that 4200 foot RWY you have climb issues, take less fuel and stop enroute unless of course your boss/client/owner is a jackass that won't listen to your safety concerns/issues.

As the Captain at one point you're going to have to put your foot down and say "That's the way we are planning this trip for operational/safety issues", period.

As a pilot you can only use the tools available to you. In some circumstances you fall in a very gray area and that's when "experience" comes in.

@ tommoutrie...

Finally if you are so intent in getting all your performance issues with a bunch of "What ifs", may I suggest you call Bombardier explain your issues and perhaps their flight science department can come up with the proper numbers for your flight.

Last edited by Jet Jockey A4; 18th Feb 2015 at 20:59.
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Old 18th Feb 2015, 19:02
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I've heard that bulls**t baffles brains. In my experience those who speak the most always seen to be simply justifying their own inadequacies.
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Old 19th Feb 2015, 07:56
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In my experience those who speak the most always seen to be simply justifying their own inadequacies.
Is that why you commented ? Especially in the Falcon short field thread ? ...
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