Have you checked performance #s?

[400A]

Note to Self: Never get in an airplane with Captain Stick Shaker.

Got that right!!! But instead, others who would not do it were terminated.

 

[FurloughedAgain]

UltraNav doesn't account for close-in obstacles.

Can you say airport analysis?
http://atlas.apg.aero/

 

[SoundBarViolatr]

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.

 

[Lead Sled]

...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

 

[Lead Sled]

UltraNav doesn't account for close-in obstacles. Can you say airport analysis?

That's even better. From what he was saying I didn't get the impression that he was going for that much detail.

 

[FurloughedAgain]

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.

 

[MoralDK]

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.

 

[Lead Sled]

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

 

[Lead Sled]

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.

 

[FurloughedAgain]

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.