Have you checked performance #s?

[HvyjetFO]

Hey all,

With all the flight tracking software out there, it's easy to see who's going where, and something that I'm curious about is how many pilots are out there going where the boss tells them to with disregard as to what the plane can actually do while maintaining high margins of safety.

For example, I fly the C650, which is a good airplane, but it definitely is a pig as far as short field performance goes. I know that anything less than 6000 feet of runway in summer heat and you better double check your numbers. Yet, I see 650s coming out of 5300 foot strips and doing 3 hour over water flights to TEB, so you know they gotta take extra gas going to a NYC area airport. Assuming they only took 4 hours of gas for the 3 hour flight they would need 4800 feet of the 5300 ft runway, assuming they had no pax or bags (unlikely). Add 4 pax and bags and your at 5150 feet. IMHO there is no margin for error here. Lose one right before V1 and you are going off the runway.

Also, I saw a 650 do a 1800 mile trip with a 100 knot headwind. Planned flight time was 4+30. I know there is no way to do this flight without landing on complete FUMES.

And when was the last time you took a look at 2nd segment?

Friendly reminder folks...get in the manuals. We keep them on board for a reason. I don't mean to come across as preaching, but it appears some people just succomb to the "it'll make it" philosophy too often.

Hvy

 

[snow-back]

Hey all,

With all the flight tracking software out there, it's easy to see who's going where, and something that I'm curious about is how many pilots are out there going where the boss tells them to with disregard as to what the plane can actually do while maintaining high margins of safety.

For example, I fly the C650, which is a good airplane, but it definitely is a pig as far as short field performance goes. I know that anything less than 6000 feet of runway in summer heat and you better double check your numbers. Yet, I see 650s coming out of 5300 foot strips and doing 3 hour over water flights to TEB, so you know they gotta take extra gas going to a NYC area airport. Assuming they only took 4 hours of gas for the 3 hour flight they would need 4800 feet of the 5300 ft runway, assuming they had no pax or bags (unlikely). Add 4 pax and bags and your at 5150 feet. IMHO there is no margin for error here. Lose one right before V1 and you are going off the runway.

Also, I saw a 650 do a 1800 mile trip with a 100 knot headwind. Planned flight time was 4+30. I know there is no way to do this flight without landing on complete FUMES.

And when was the last time you took a look at 2nd segment?

Friendly reminder folks...get in the manuals. We keep them on board for a reason. I don't mean to come across as preaching, but it appears some people just succomb to the "it'll make it" philosophy too often.

Hvy

Correct me if I'm wrong, but 5150' is less than 5300', which falls within the performance parameters and therefore should not run off the runway. I guess it has to do with your comfort level, but the "numbers" are what we have to calculate our performance. Where do you draw the line if 5150 isn't enough? Do you pick an indiscriminate point or a certain percentage below max performance? Are you intimately familiar with your aircraft's capabilities? Personally, I like as big a safety margin as possible, but if the numbers get tight, I am proficient and confident enough to take them up to the limit...notwithstanding extraordinary factors.

BTW, our flight department adheres strictly to the performance limitations of our aircraft and will adjust any flight accordingly without fear of reprisal.

 

[HvyjetFO]

You are absolutely correct in that the book numbers are the limit. Yes, I am confident in my abilities as well to handle such situations as well. However, my point is that I don't believe people are aware of and/or ignoring a lot of these "gotchas" out there. I did neglect to mention that the numbers in my earlier post was for "bleeds off". With bleeds on it increases the distance by 2%, so thats where 5300 ft came into play. It would be right at the limit if one didnt check the numbers and forgot to turn the bleeds off.

All said it sounds like we're on the same page.

Regards,
Hvy

 

[Hawker800]

operate a Hawker 800 in FL. Deal with this issue all the time during summer months. Have had no problem with the boss.

 

[HvyjetFO]

Absolutely! These issues have never created a problem with the boss either. As a matter of fact, when they realize exactly how deep you get into it to guarantee their safety, it's added job security.

 

[Raskal]

Tell you what, my comanpy operates hawkers to the limit constantly...I don't like it either. It's legal, but all the same. Example, east hampton I know is full of corporate aircraft in the summer pushing it with weight, especially luggage. We call the perf charts "voodoo numbers", lets face it folks, I doubt any of us are as quick as the test pilots on that day of testing in a brand new aircraft with no squawks and perfect brakes. Frankly, a lot of what goes on with these arcraft and private operators is a joke...anything so as to not inconvenience the pax, right?

 

[peter185]

Aren't the refusal #'s calculated so that you could have an emergency requiring an abort at V1. Then the numbers are calculated for you having three seconds to make your decision to abort before taking any steps towards actually aborting. Three seconds is a lifetime in my opinion. Maybe this is not how it is for corporate aircraft, but in the T-1 (beechjet) this is how the accelerate stop distance was calculated.

 

[Lead Sled]

We call the perf charts "voodoo numbers", lets face it folks, I doubt any of us are as quick as the test pilots on that day of testing in a brand new aircraft with no squawks and perfect brakes.

That's not how those numbers are generated. All of the performance numbers in the AFM should easily achievable by the "average" guy in the "average" airplane. However, you have to understand that if you want to achieve book performance you have to fly by the book - using book techniques and procedures. Unfortunately, this is a foreign concept to many pilots. Things like rotation rates have a significant effect on takeoff performance. Your manual probably tells you how fast you need to raise the nose and to what angle. Do you know what it is and more importantly, do you do it each and every takeoff? Or do you simply punch "go-around" and rotate into the V-Bars?

Do you use the climb profile and power settings shown in the performance charts? Or do you use some personal speeds that "seem to do better". When it comes the TFE731 engines (non-fadec) that many of us operate, do you set climb and cruise power according to the N1 charts in the flight manual or do you use some arbitrary temperature settings?

Do you do your flight planning based on actual flight manual numbers or do you figure on so many pounds for the 1st hour, so many the second hour, and so on? (That's a good way to double check your numbers, but definately not the best way to calculate the fuel and flight time if you're planning on flying out near your range limits.)

You know what your airplane weighs, are you honest about what everything else you have onboard weighs? In some airplanes weight and balance can be a significant issue, in others, it isn't. If you consistantly run around out of CG or a little overweight you're exposing yourself to a lot of personal liability that you probably aren't ready to deal with.

There is absolutely no problem with flying out near the edges of the performance envelope - as long as you remain in the envelope. The problem is that many pilots don't really know where the edges actually are, so that have no idea when they've gone beyond them.

Frankly, a lot of what goes on with these arcraft and private operators is a joke...anything so as to not inconvenience the pax, right?

Most of the operators that I know operate thier aircraft in a very consciencious and professional manner. Unfortunately, there are some bozos out there too. Sloppy techniques and procedures don't necessariliary manifest themselves until you take the airplane out near the edges of the performance envelope.

LS

 

[Raskal]

Thanks LS, that was a well-written and thoughtful post, unlike my own sarcastic one. I will try and respond with less of the just-got-back-from-a-sh!tty-trip perspective.

I know what you're saying, and yes, I'm familiar with everything you're talking about. In some cases my company feels it knows better than the book, but we operate all our aircraft by the manual when the brass isn't on board.

Weight is my concern. Our company claims to support us, but we are often in arguments with pax over luggage size, weight, placement etc...while the company just plays neutral-missing opportunities to educate the pax choosing rather to make the pilots look conservative and unreasonable. Yes, we eventually win the arguments with the pax, but how long was it or how long will it be before somebody just gives a little to end everything and go home? I've seen it, but refuse to be a part of it.

We get this extremely detailed, down to the foot and pound performance chart out and very carefully try to folow these crazy-small grid lines to eek that little extra bit of distance out of the plane...yet, how many times has anyone really seen pilots weighing the luggage or the pax? But somehow we can use every feet of the "value of d" (for the hawker guys). When one really considers it, it gets silly. Somebody aborts at east hampton (4255ft) in a hawker, they're goin off the end, then how are those little perfomance charts gonna hold up? Will they save any problems with the feds? I'm just saying it's worth a thought.

 

[shiznitobam]

...We get this extremely detailed, down to the foot and pound performance chart out and very carefully try to folow these crazy-small grid lines to eek that little extra bit of distance out of the plane...yet, how many times has anyone really seen pilots weighing the luggage or the pax? But somehow we can use every feet of the "value of d" (for the hawker guys). When one really considers it, it gets silly. Somebody aborts at east hampton (4255ft) in a hawker, they're goin off the end, then how are those little perfomance charts gonna hold up? Will they save any problems with the feds? I'm just saying it's worth a thought.

I love it. We measure with a laser and cut with an axe. It doesn't take much to throw the performance numbers right out the window.

 

[400A]

Led Sled

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.

 

[Hawker800]

I explained to my boss that my job is to keep him safe no matter what. I get paid to say not to him on occasion. A phone call will take care of most issues. No one will care next week. If I screw up and put him in the trees, it will make a big expensive difference to a lot of people for a long time to come. After this little explanation, I have no issues. Communicate communicate.

 

[ultrarunner]

I don't cheat on the runway numbers or climb segment numbers. Never had, never will. I'm also a big fan of 'reduced decision speed' as I get closer to the runway limit.

If we're hot and high, or other issues such as this where a departure at a cooler temp makes the difference, the boss is briefed on this. That does not happen often, but when it does, it's briefed upon arrival.

It's all about communication, simple as that. Keeps everyone safe AND happy!

 

[TimsKeeper]

bad performance

I just ended a position due to an old aircraft underperforming; causing countless operational problems, thus causing me daily headaches with management.

If your aircraft is underperforming the "book" numbers you have a responsibility to not continue the behavior of take-offs on the performance limit without making adjustments or finding out what is causing the reduced performance.

The start of this thread was not forgetting to look at the info. Even on a 12000 ft runway I've never been part of a crew that didn't look up speeds and have the tofl written down somewhere. I'm all for lazy, but that's a little irresponsible....it's not optional to know this information.

If the original poster is saying you look up the numbers and see you can't do it and go anyway...that's just wrong and I wouldn't ever intentionally do it.

I'm looking forward to being an old pilot.

 

[FurloughedAgain]

I could be wrong, but I think he was looking at runway numbers and climb gradients more than speeds.

Even some east-coast airports have SIDs with climb gradients that could yield significant weight penalties. Far too many people ignore gradients assuming that two engine climb will clear the obstacle.

Integrity isn't free. Sometimes you have to make the hard decisions.

 

[400A]

I could be wrong, but I think he was looking at runway numbers and climb gradients more than speeds.

Even some east-coast airports have SIDs with climb gradients that could yield significant weight penalties. Far too many people ignore gradients assuming that two engine climb will clear the obstacle.

Integrity isn't free. Sometimes you have to make the hard decisions.

KPDK 20L is a great example of that.

 

[hawkerjet]

The initial post states that since you're going to the NYC area you've got to take extra gas. Why? Does the arrival weather always dictate the need for an alternate? Problems with Flow Control? If you're adding to the numbers arbitrarily by not following the AFM and it's numbers, and adding fuel because you're going to a metropolitan area then why wouldn't you're numbers be high. There is really no gray area here if you do things the right way. And I'm not knocking you at all. I have gone from KSMO to TEB in a westwind many times non stop without checking the AFM because we did it so much. I new I couldn't do it above a certain aircraft weight and above a certain temperature. This is a common complacency that pilots fall in to and hopefully we are smart enough to get out of it before something bad happens.....

 

[ksu_aviator]

Maybe I'm a geek, but I got tired of trying to trace those stupid lines with a pencil that has a 200 foot wide tip. So, being the geek that I am, I sat down this week and pre-calculated performance for Sea Level to 5000 at 1000 foot incriments and from -15 degrees to 40 degrees in 5 degree incriments.

Now I have a chart that I can quickly reference that gives me my WAT limit, Accel-go/stop and climb % as well as my power setting.

Keep in mind, this is a quick reference chart that will almost never exactly match any airport and temperature. However, it does tell me what I can expect at an airport that my boss wants to fly into.

 

[GoingHot]

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

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

 

[Lead Sled]

Maybe I'm a geek, but I got tired of trying to trace those stupid lines with a pencil that has a 200 foot wide tip. So, being the geek that I am, I sat down this week and pre-calculated performance for Sea Level to 5000 at 1000 foot incriments and from -15 degrees to 40 degrees in 5 degree incriments.

Now I have a chart that I can quickly reference that gives me my WAT limit, Accel-go/stop and climb % as well as my power setting.

Keep in mind, this is a quick reference chart that will almost never exactly match any airport and temperature. However, it does tell me what I can expect at an airport that my boss wants to fly into.

Can you say "Ultra-Nav"?

 

[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.