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Have you checked performance #s?

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Concur, Sadly.

Sadly, I concur. Performance Calculations and SOP seems so lax in the civilian world. I bumped heads with a Captain at my first civilian job just because he insisted the Lr55 made the heavy departure out of Aspen countless times before just fine, clearly not understanding that the performance numbers are based on single engine performance. After exhausting my case, I ended up calling it in and Management made him put in a fuel stop.
 
...clearly not understanding that the performance numbers are based on single engine performance.
Actually, DP Climb Gradients are based upon "all engine" operations. Period, end of discussion. The takeoff performance charts in Part 25 transport category business jets only gets you to to 1500' AGL - in other words, pattern altitude. At that point you either come back around and land or you need to have the performance to do something else. This is a "corporate" forum so I'm assuming we're talking Part 91 operations here. Under part 91, you have no obligation to be able to achieve the required climb gradients after the loss of an engine; however, common sense and professionalism requires that you have a plan B just in case... This is where the "alternate" departure procedures come into play for 121, 135, and savy 91 operators. Oh well, this will probably start another firestorm. I recommend doing a search on Aspen. We've plowed this ground many times before.

LS
 
LeadSled said, "common sense and professionalism requires that you have a plan B just in case". Couldn't have said it better if I tried.

Sure, part 91 operators are not required to comply with climb gradients -- and those gradients are all-engine anyway! (We don't even have charts for that!!)

When we cut through all of the layers of complexity though, the PIC is ultimately responsible for the safe conduct of the flight. It is an issue of integrity.

OK. So there is a climb gradient on departure due to an unknown obstacle or terrain. As a responsible PIC I want to be able to clear that obstacle even in the worst case scenario -- i/e IMC conditions, engine failure at V1, loss of radio communications, and an inability to make a quick return (debris on the runway perhaps?)

Overkill? Perhaps. But there is some comfort in knowing that regardless of the situation, the aircraft should have the performance to clear the obstacle...whatever it is.

Now the fuzzy area is between 2.4% (part 25 certification requirement) and 3.3% (minimum gradient reflected by TERPS on departures).

That is the area where Ultranav won't help you and where airport analysis is worth it's weight in gold.

Look. At the end of the day flying airplanes is how I put food on the table for my family. I'm not going to do anything to jeopardize my mortality or my certificates. There's always another job out there if some operator is asking you to compromise safety.

By the way, You can run the numbers for a gradient at any altitude. Simply back down 1500 feet in the charts.

For example, if the airport is at sea level the charts will give you info to 1500 feet. If the gradient requires (for example) 800 ft/nm to 10,000 ft... simply enter the chart at 8500 ft (10,000 - 1500).

Even if it's VFR, clear and a million, have a plan. After all, you don't know what that obstacle is... a tree? Powerlines? Radio antenna? Rising terrain?
It's not worth a violation or an accident to find out the hard way.
 
I don't know how many times I've been told by a newbie that the charts aren't correct or that we shouldn't be doing something even though the charts say it will work. I have found that most of the pilots I have dealt with are very conscientious about checking performance, and have met very few cowboys. I have heard lots of talk about "those guys" that are cowboys. I just haven't actually come across "those guys" in person.
 
By the way, You can run the numbers for a gradient at any altitude. Simply back down 1500 feet in the charts.
That's not quite correct. You really can't extrapolate those charts - there are configuration, bank angle and speed constraints that make would make them inaccurate. The takeoff performance charts are good to 1500' AGL. I've had folks (even some factory demo pilots) try and give the same explaination - it just doesn't fly. The real answer is airport analysis, it's too bad that many pilots aren't aware of this.

LS
 
I don't know how many times I've been told by a newbie that the charts aren't correct or that we shouldn't be doing something even though the charts say it will work. I have found that most of the pilots I have dealt with are very conscientious about checking performance, and have met very few cowboys. I have heard lots of talk about "those guys" that are cowboys. I just haven't actually come across "those guys" in person.
Unfortunately, there are plenty of cowboys out there.
 
Really? You'll have to explain that to me.

The chart doesn't know what altitude your departure airport is, so if you tell it that you need to maintain 800 ft/nm to 10,000 feet and you are able to achieve that from 8500 to 10,000...then it stands to reason that you would be able to achieve it at less than 8500. Right?

I'm not questioning you, just wondering if I correctly understand the second-segment climb tables. (Lear takes 2nd segment all the way to 1500)

As for airport analysis, I agree 100%. I used it for years in part 121 and our department recently started using it part 91. I feel much more comfortable with their calculations then with me ham-fisting the charts to get runway limit or climb limit.
 
Really? You'll have to explain that to me.

The chart doesn't know what altitude your departure airport is, so if you tell it that you need to maintain 800 ft/nm to 10,000 feet and you are able to achieve that from 8500 to 10,000...then it stands to reason that you would be able to achieve it at less than 8500. Right?

I'm not questioning you, just wondering if I correctly understand the second-segment climb tables. (Lear takes 2nd segment all the way to 1500)

As for airport analysis, I agree 100%. I used it for years in part 121 and our department recently started using it part 91. I feel much more comfortable with their calculations then with me ham-fisting the charts to get runway limit or climb limit.
There are several reasons you cannot use AFM 2nd segment climb data in meeting TERP's criteria. First, all the one engine-out climb flight path data (1st, 2nd, and final segment climb charts) are only good to 1,500 above the runway (however, some manufacturers have gone beyond this point up to 3,000 to 5,000 feet) and CANNOT be used to the heights demanded of certain DP's such as is the case of KASE, 7,800 ft to 14,000 ft. 2nd segment climb data is generally only valid to 400 ft above runway, the point where 2nd segment ends. Second, the differences in climb terminology. Most 2nd segment climb gradient charts in AFM's give the available NET climb gradient so that when you apply this to the flight path charts or computer program you get a resulting NET flight path. TERP's climb requirements are based on actual performance, NOT an already an already reduced NET climb gradient. Then there's the consideration of 5 minute limitation on takeoff thrust. Many DP's require climb gradients to significantly high altitudes that would exceed the limitation on takeoff thrust, not to mention a shallowing climb gradient due to density altitude changes as you climb. Remember if you try to use 2nd segment climb, you'll only meet that climb gradient if you keep V2, takeoff flaps, and takeoff thrust and that climb gradient is generally valid only at 400 ft above the runway. Additionally, the charts assume essentially "wings level" flight (I don't remember the exact bank angle limit and my files are at home.) and many DPs involve turns that would exceed these bank angle limitations.

Aircraft "1-engine out" part 25 certification requirements only get us to 1500' AGL on takeoff, after which we immediately transition into the enroute all-engine TERPS climb. I guess that the original intent was that if we could safely get up to pattern altitude after losing an engine on takeoff we could bring the airplane back around for a landing. The enroute climb phase is based on all engine operation. If an engine is lost during that phase, it is an emergency, justifying the use of "alternate departure procedures" as provided by folks like APG or Jeppesen. (The alternate procedure for ASE isn't all that limiting, but it's a pretty demanding procedure - one best practiced a time or two in the sim.)

LS
 
That makes perfect sense, thanks. So for those folks who do NOT have airport analysis and whose manufacturers do not provide all-engine climb data, how do they ensure they can comply with a TERPS climb gradient?
 
That makes perfect sense, thanks. So for those folks who do NOT have airport analysis and whose manufacturers do not provide all-engine climb data, how do they ensure they can comply with a TERPS climb gradient?
Oh well, that's easy - all you have to do is go to your flight manual and find the "All Engine Operating Enroute Climb Chart". Oh wait, they don't provide us with that information in the flight manual. Hmmm, I guess you essentially have to determine the required rate of climb based upon your climb speed (a table is provided on the DP chart) and using all of your skill and experience as a pilot to guesstimate if you will be able to achieve the required climb rate. (I don't have to stretch too much - as I remember, the DP at ASE only required a climb rate of about 1600 fpm at 14,000' MSL. The stuff I've been flying will normally do about twice that. ) I guess what I'm trying to say is that you really need to have an alternate procedure available to you in the event of an engine loss - just like the 121 guys have.

LS
 
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Terps

Actually, it was a p135 mission. But good points nontheless.

Actually, DP Climb Gradients are based upon "all engine" operations. Period, end of discussion. The takeoff performance charts in Part 25 transport category business jets only gets you to to 1500' AGL - in other words, pattern altitude. At that point you either come back around and land or you need to have the performance to do something else. This is a "corporate" forum so I'm assuming we're talking Part 91 operations here. Under part 91, you have no obligation to be able to achieve the required climb gradients after the loss of an engine; however, common sense and professionalism requires that you have a plan B just in case... This is where the "alternate" departure procedures come into play for 121, 135, and savy 91 operators. Oh well, this will probably start another firestorm. I recommend doing a search on Aspen. We've plowed this ground many times before.

LS
 
Ultranav

KSU pilot may be able to produce this information for free, however in my opinion Ultranav is worth every penny and thensome.

I remember back in the Hawker charter days Ultranav giving me information within a minute to make determinations that would of taken 15 minutes or more if I pulled the Manuals out. Now if you have to do this once or twice yeah Ultranav seems a bit extravagent. But when you are flying charter on a daily basis and some of it includes high-altitude Colorado airports with constantly changing winds and other conditions it makes a heck of a lot more sense.

It's an extremely useful tool and quite honestly 1200 bucks isn't that much when you're dealing with million dollar airplanes.
 
I'd like to point out that airport analyses are company specific. You have to pay a vendor to develop the analysis for the specific airport and your airplane. I agree they're great, but the cost is prohibitive.
 
KSU pilot may be able to produce this information for free, however in my opinion Ultranav is worth every penny and thensome.

I remember back in the Hawker charter days Ultranav giving me information within a minute to make determinations that would of taken 15 minutes or more if I pulled the Manuals out. Now if you have to do this once or twice yeah Ultranav seems a bit extravagent. But when you are flying charter on a daily basis and some of it includes high-altitude Colorado airports with constantly changing winds and other conditions it makes a heck of a lot more sense.

It's an extremely useful tool and quite honestly 1200 bucks isn't that much when you're dealing with million dollar airplanes.

Hugh Johnson said:
I'd like to point out that airport analyses are company specific. You have to pay a vendor to develop the analysis for the specific airport and your airplane. I agree they're great, but the cost is prohibitive.
Ultra-Nav is great but it's only 1/2 of the correct solution. The real answer is to impliment both Ultra-Nav and airport analysis. Airport analysis will tell you how much you can carry and give you an alternate departure procedure if necessary and Ultra-Nav will quickly give you the numbers and speeds.

I'll have to disagree with Hugh Johnson, earlier this year I entered into an agreement with APG was for unlimited monthly usage for 1 airplane and the cost was less than $80 per month - hardly a cost prohibitive item.

LS
 
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Very well stated. Some guys are over cautious to the safe side, and some throw the book right out the window.

I wish I had a dollar for every King Air 200 guy I have heard say "The Military operates them at 14,000 lbs" or what ever the actual number is.

Yes they do, but they have a type, 2 crew, and have trained in it at that weight...... you?

Other guys are always looking for a reason not to fly.

I know of one guy who regularly departs an airport with the stick shaker going off.

That's interesting...didn't know there was a stick shaker in a King Air 200.
 
Nope.

1. They don't have my aircraft.

2. I'm not spending $1200 to get information that I can produce for free!

I am glad you are not flying with me when you pull out the AFM, slide ruler and what ever else you need to get a number while your passengers and I wait. What do you do when conditions change at the last minute for example: it starts raining, they show up with extra passengers or runway change etc?

We use all available information, including Ultra-Nav.
 

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