JohnBurke

Which is why an obstacle analysis for a runway takes into account (wait for it) OBSTACLES.

You don't really think you're being given a higher clean-up altitude for something else, do you?

You have 300 pilots and no training department? Fractional provider, then?

The concept of having a higher cleanup altitude is that you maintain V2 to the cleanup altitude. You don't accelerate at 400'. You accelerate at the acceleration altitude. You're in second segment until then. Remember that second segment has a climb gradient. Third does not. Think about it.

Keep doing it however your company wants it done. Odds are that you'll be fine. Take a chance. Live a little. Forget that we ever had this conversation. Life's too short to worry about flying into a few rocks.

Let the more experienced pilots, the ones you cited who were giving a lot of thought to their engine-out performance, worry about details like this.

2StgTurbine

Um, what I and PerfInit were talking about there is something completely different than what you are. What we were talking about was if the ORD 9 departure says maintain a 450 ft/nm until 3,000 feet, that it does not mean we need to maintain that if we are operating on one engine. That climb gradient is for a noise abatement procedure. If you have an engine failure, you will climb below that gradient, but you won't hit anything. In the class I was teaching, the pilots thought that they couldn't accept that departure at higher weights and would request a different departure or would take on less fuel. So it has nothing to do with clearing any obstacles.

Thanks for again stating facts that no one is disagreeing with. Again, my issue is my company has us start the third segment at 400 ft AGL all the time, but the runway analysis we use maintains the second segment until a much greater (and different for each runway) altitude. Our SOPs conflict with our performance data if we have an engine failure above 400 ft, but below the APG acceleration height.

The only way I could see to resolve this was to get rid of our 400 ft SOP and adopt and SOP that matches the APG acceleration height. This would cause other implications to the way we operate this aircraft so it will require changes to several other procedures and checklists. That is a big organizational change and I wanted to see if anyone else has ever come across something similar and found another way to solve this problem.

At no point did I say that I don't understand aircraft certification standards, nor do I believe I have said anything wrong about certification standards and obstacle clearance procedures. I have also not said that I am disregarding the APG runway analysis. I am actually following them which is causing me to go against our SOPs and requires me to explain to a lot of the FOs I fly with why I am doing it, and most captains don't understand why I don't retract the flaps until I reach the APG acceleration height. Maybe I should just insult people and talk down to them if they don't agree with me, or be like you and insult and talk down to people who actually do agree with me.

JohnBurke

You are saying that at an airport with diverse climb criteria and no obstacles, you are receiving higher obstacle clearance engine-out criteria from APG? Give an example.

You cited Aspen, previously.

You're saying now that you have obstacle analysis data provided for "noise abatement procedures?"

Departures not specifically obstacle departures may be for reasons other than noise; traffic routing, conflicting airspace (overflight of a busy approach corridor, for example), and other reasons require crossing restrictions for a departure, when assigned (and remember, accepted).

When given an obstacle analysis, the analysis isn't computing second segment to meet departure procedure crossings. It's giving you obstacle avoidance criteria. That is the purpose of continuing second segment to the cleanup altitude, or for telling you that you're unable to accept a particular procedure under given conditions (weight, altitude, temperature, and configuration limitations, etc, on a specific runway.

Of course you get different obstacle clearance altitudes for different runways. The analysis is for a specific runway at a specific temperature and altitude. The data you're being given for engine-out climb, however is not to meet noise abatement. It's to clear obstacles. That's the purpose of a runway and obstacle analysis. That's why you've got it.

Again, it sounds like complying with the safety information you're given may be too taxing for you. Carry on as if the matter had never occurred.

2StgTurbine

Yes I am. For example off of runway 7 at KDEN, APG gives a flap retraction altitude of 7,331 ft MSL which is 1,897 ft AGL. As far as I can tell, there are no close in obstacles. The way I comply with this is to keep my flaps at takeoff until 7,331 ft MSL in order to ensure I have the required climb performance if I have an engine failure after V1, but below the APG flap retraction altitude. Since this differs greatly from our SOPs, it requires a lot of extra briefing and modifying of our after takeoff flow in order to prevent the PM from retracting the flaps too early, or the PF from doing our normal two engine acceleration which would cause an undesired aircraft state with our stabilizer. Since I have to make this briefing for every departure, it would seem that the SOPs should be modified so I don't have to constantly brief this and so that all of our pilots understand that the APG runway analysis dictates our flap retraction altitude, not what the manufacture used to meet the certification standards.

No, I am not nor have I ever said that. What I and PerfInit were talking about in a sidebar was the belief some people have that they must comply with the climb gradients listed on the FAA/Jeppesen charted departure procedures even on one engine. For example at KDEN, the BAYLR 3 RNAV departure off of runway 8 requires a climb gradient of 400 ft/nm until 5,934 ft MSL. That climb gradient has nothing to do with clearing obstacles since the non RNAV Denver 8 departure off of that runway simply requires the standard 200 ft/nm. In the case I was talking about with PerfInit, there were pilots who thought they could not file the BAYLR 3 RNAV departure unless they could maintain 400 ft/nm on one engine. That is a different topic than the original one I started this thread about and had nothing to do with runway analysis programs.

Again, the only way you seem to know how to teach is to belittle other people. In this case, your characterization of me is wrong. You are the one who seems to be confused on what I have been talking, but I will give you the benefit of the doubt that you are having difficulty understanding the points I have expressed due to the medium.

JohnBurke

As far as you can tell? APG performs a runway and obstacle analysis, and your assessment is "as far as I can tell?" That settles it, then. It seems you know more than APG. You might be able to make a small fortune supplanting their business and your overhead will be quite low. Where as they must spend a great deal of time and expense to make those determinations, you can simply look and say "nothing there as far as I can tell." You've got it nailed. Congratulations.

Close-in obstacles may not be the reason, and an analysis isn't just looking at immediate obstacles. There are a number of reasons that a level off altitude may be assigned as part of a runway analysis. Not all of them are next to the airport. That doesn't matter, because as far as you can tell, there are none, and that's good enough.

Have you looked at the takeoff minimums and gradients for runway 7 at KDEN? Have you noticed that for each departure, runway 7 is cited as NA-ATC, and that there are departures depicted for each runway, including 26...except runway 7? The takeoff minimums and obstacle departure procedure for runway 7 simply says "Climb on a heading between 315 clockwise to 220 from DER. All other courses, climbing right turn, thence direct DEN VOR/DME holding pattern (hold South, right turns, 343 inbound) to 16,500 before proceeding on course."

Where is the route description for runway 7 for the BAYLR3, BRYCC3, CONNR3, COORZ3, EEONS5, EMMYS5, EPKEE3, EXTAN4, FOOOT3, JMPRS2, RIKKK3, SOLAR3, SPAZZ3, or STAKR3 departures? You won't find it. It's per ATC, in which case ATC takes responsibility for your path. ATP publishes a minimum for your own use, for safety. Ignore it at your peril, as your published procedures give you no guidance in that regard.

The DENVER 8, PIKES7, PLAIN7, ROCKI2 uses radar vectors, for which ATC takes responsibility, and in which case your analysis will still provide your minimum cleanup altitude for an engine-out. Altitudes provided are for more than just trees and rocks. Departures are assigned for more than just noise. Traffic flow and congestion are also applicable, and runway 7 blasts off a number of directions, dependent on ATC assignment and vectors, and crosses the departure path of a number of other runways. There's more to the designing of your runway and obstacle analysis than what you see out the window, or think you see...but then as far as you can tell, it's no big deal, right?

As you should.

SOP means standard procedure. If you're given something which is not standard, then the SOP is irrelevant. Simply because you do something in Jamaica or Miami doesn't mean you do the same thing in Denver or Lima, Peru. You fly the departure for the location where you are. This is obvious, is it not?

A "lot of extra briefing?" Your'e briefing the material that you're given for the departure. This isn't rocket science. You're given a nonstandard value for cleanup on an engine-out on departure; that's what you brief. If you have an immediate left turn after takeoff, even though you don't normally do that, you brief that, too. Brief what's appropriate for that specific runway on that specific day. If your company subscribes to data that tells you to climb to 7,331' before cleaning up the airplane, then do that. Not really that complicated.

It's too difficult for the pilot flying to refrain from falling back on habit and retracting flaps at 400? Even though the pilot has briefed the departure? A pilot can't brief a departure and fly it as briefed? Truly amazing. What is such a pilot doing in the cockpit in the first place??

You assert that the pilot monitoring might retract the flaps too early? Your monitoring pilots don't retract flaps on command, but simply to it on their own at 400'? What kind of a show are you running, there? People simply act willy-nilly, doing their own thing, freelancing in the cockpit? Who is in charge? You're actually worried that the PNF/PM might actually go off on his own, retracting flaps at 400' even though 7,331 has been briefed, because that's what he does at some other airport? You have bigger issues than simply using APG's data. You have a major breakdown in cockpit discipline. Apparently no standard, either.

What altitude does your APG program give you for a departure off runway 8 on the BAYLR3, with an engine-out? Let's stick to the discussion, shall we? You're attempting to drift far afield. What pilots might want to do for any other reason is irrelevant. The thread, and your question regards your "SOP" cleanup altitude of 400,' vs. runway and obstacle analysis data provided for you by APG.


Is it difficult for you to "constantly" give a briefing that addresses actual takeoff conditions? Rather stick to a canned one, would you? Sounds tough.

You do understand that what was used to meet certification standards is irrelevant with respect to where you bring the flaps up for a departure at a given airport, don't you? Every bit as much as demonstrated crosswind has nothing to do with what the aircraft can actually handle. That's a value used at the time of certification, but in no way was ever intended to imply that the aircraft should be operated in that manner. In fact, V2 for certification purposes is provided to 400 feet as a MINIMUM. It's not a fixed or hard altitude, and it's fullly expected that where a higher altitude is appropriate given terrain or other reasons for cleaning up later, that you'll do that. It's what you're paid to do; fly the airplane safely in real world conditions, not living in the past based on an arbitrary minimum number used to demonstrate minimum performance before the airplane ever went into production.

Then again, all that briefing, all that flying, all that wranging of the PM to keep him or her under control, is clearly a difficult burden on you. Perhaps you should blindly stick to a 400' flap retraction altitude, ignore the data that's given you, and move on with your life. Probably, nothing untoward will happen. Probably.

Adlerdriver

John,
This is a meeting place largely for professional pilots to exchange information on various industry topics. Do us all a favor and conduct yourself accordingly. Frankly, you're embarrassing yourself. Perhaps all you've known is instruction via sarcasm, ridicule and condescension so those are the only tools you use. There are better ones.

I have to give 2Stg some serious kudos for sticking with this thread as long and as patiently as he has.

Clearly there are some limitations to communications using this medium. Misunderstandings aren't always the other guy's fault or due to his lack of knowledge. It's a two-way street. You are definitely a major part of any communication issues occurring in this thread - trust me.

For example: When 2Stg said "as far as I can tell, there are no close in obstacles". I took that to mean when he looked at the information he had available he couldn't pinpoint what was driving the higher flap retraction altitude. I didn't assume (as you did) that meant he wasn't going to use the runway analysis and blow off the higher retraction altitude.

You did assume that, however, and we all get to enjoy a ridiculous, 5-paragraph diatribe lecture on an unnecessary tangent. All that thanks to your inability to understand the written word or clarify what you think you read.

Just another data point on performance data: I'm on my third 121 airline and the data we used at all three had no specific information on obstacles, terrain or why there might be a higher than normal EO accel altitude. We just get the altitude. If I wanted to know why, I would probably have to grab a sectional and see what was out there. After doing that, I might find nothing specific. So, I might say something like.... "As far as I can tell, there are no close in obstacles". Maybe it's due to terrain or an obstacle I didn't find. Just because I didn't find the specific reason it's computed doesn't mean I wouldn't use it.

Adlerdriver

2Stg,
I've been following this thread, but stayed on the sidelines after the first couple of posts because I don't have any experience with business jet operations. I'm also unfamiliar with the APG product.

From what I can tell as I read through most of this, it seems like the very low (from my experience) normal acceleration altitude of 400' your company uses is at least part of the issue. If the APG data is almost always driving you to a higher EO accel altitude, it certainly sounds like it would streamline your operations to match them up (if there is a typical EO for most non-mountainous takeoffs). Maybe that's not possible due to aircraft limitations or other issues. I don't claim much expertise there. I've been fortunate to operate aircraft with enough excess performance that we had the flexibility to do that.

In my experience, I normally use one of two normal acceleration altitudes. 3000 AGL for NADP-1 and 1000 AGL for NADP-2. Our EO accel altitude is 1000 AGL for simplicity. Under extreme situations, it could be lowered all the way down to the certification altitude of 400 AGL. I've never heard of that happening in practice. Occasionally, the runway analysis produces a non-standard EO accel altitude higher than 1000 AGL, so we brief that and would use it in the event of an engine failure prior to that altitude.

I fly international mostly and use NADP-1 often. With a planned normal acceleration altitude of 3000 AGL, I've never seen an EO accel altitude higher than our normal 3000 AGL. With an NADP-2, non-standard EO accel altitudes may be slightly higher than the normal (maybe by a few hundred feet).

However, with a non-standard EO altitude of say, 1500 AGL, we would still use the normal 1000 AGL (if flying NADP-2) unless we had an engine failure.

Questions:
Does the APG output always supply both a normal all-engine accel (flap retraction) altitude and an engine out accel altitude? Sometimes it's hard to tell which one you're talking about. Perhaps you could refer to them using "normal" and "EO" for clarity.

When you say APG gives a flap retraction altitude of 7331 MSL above, is that normal or EO?

JohnBurke

That really depends on the program in use. I've used data that tells me it's the fifteenth obstacle that's the problem, and is quite specific. Ultimately, it doesn't matter. If the analysis states that a particular altitude is required, that's the altitude to which one is going engine-out.

With a NADP-1 based at 3000 AGL, then one may be in the position in most places of being above a non-standard obstacle altitude as one is flying V2 or V2+10 to the NADP-1 acceleration altitude. Worse case one might pitch slightly for V2 if necessary, and level at the standard acceleration height, or higher as given by obstacle analysis data. Such is the case in most turbojet operations. In many light business jets, adequate thrust exists where climb is seldom a problem anyway.

Dogged adherence to a 400' altitude, or the assertion that briefing a different altitude is too difficult, or that the PM might forgo a flap command and raise them on his or her own simply because 400' has come and gone, indicates a much larger problem in the cockpit.

Adlerdriver

I'm not familiar with "non-standard obstacle altitude". Is that just another way of saying the higher than standard Engine Out acceleration altitude provided by the runway analysis?

Actually, on the 777F, we maintain V2+15 up to V2+25 for a normal takeoff (NADP 1 or 2). For engine failure on takeoff, we climb at the speed engine failure occurs (min V2, max V2+15).

Agreed.

Since you seem very familiar with the APG output, maybe you can answer this. What I'm not really understanding about 2Stg's runway 7 KDEN scenario above is the 7331 MSL flap retraction altitude provided by APG. Is that an Engine Out acceleration altitude or is APG providing variable normal all-engine acceleration altitudes in addition to the EO for every takeoff?

If it's just an EO acceleration altitude, then I think I disagree with his plan to climb to that altitude on all engines in case he experiences an engine failure. I've never used an EO acceleration altitude in that way.
If I have a non-standard EO acceleration altitude provided by the runway analysis, I still begin acceleration at the normal all engine altitude unless I experience an engine failure.

If I do have an engine failure: If I'm already above EO accel altitude (maybe on NADP-1), then I abandon my NADP-1 and immediately begin acceleration. If I'm below EO accel altitude, then I keep climbing until I get there. If I've already begun to accelerate (his 401 foot scenario) but haven't moved my flaps, then I pitch back to V2+15 and climb to EO accel altitude. If my flaps are tracking to the next setting, I pitch to hold maneuvering speed for that flap position and climb to EO accel altitude.

JohnBurke

Yes. In your own case, whereas your normal acceleration altitude for clean up is above most of the altitudes that might be prescribed for a non-standard engine-out scenario, then the point for you is generally irrelevant, as you're already climbing to a higher altitude to clean up.

In the 747-200, V2 to V2+10 to 1000 AGL on a NADP-2, or to 3000 AGL on a NADP-1. Both the speed and the altitudes, of course, are a company prescription, rather than a hard number attached to the aircraft industry-wide. Same; if an engine failure occurs, then it's V2 to V2+10. If it occurs early, such as on the takeoff roll, then it's pitch to nine degrees and wait what feels like a long time for V2 to arrive. It will get there eventually.

I was hoping he would provide additional input. It was his example.

That's largely because the engine-out acceleration altitude provided on a runway analysis is generally well below your normal clean-up acceleration altitude on a NADP-1, if you're using 3,000' AGL.

Depending on your company procedure for a NADP-1, your new acceleration altitude might be higher than a standard cleanup for the NADP-2. I've had that on various occasions, and simply climb to the altitude prescribed by the runway analysis for cleanup, before initiating my acceleration and cleanup. Conversely, when heavy in locations such as Afghanistan, I've kept the climb going longer and higher with surrounding terrain.

That's reasonable, but a wiser course in my opinion is simply not to accelerate until the altitude prescribed by the obstacle analysis.