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Comment Re:Data data everywhere and not a drop to think (Score 1) 366

In fact you can firewall it. All modern (since about the '80s) engines are computer controlled. The firewall position produces thrust as a function of mode. TOGA for takeoff and climb for, well, climb and cruise. Even idle thrust is a function of configuration- if the flaps are out or not, on the ground or not, is anti-ice on, is there a high demand for bleed air.

Comment Re:Data data everywhere and not a drop to think (Score 1) 366

I are a pilot. Nowadays, butts are just given an assumed weight. Not sure how much exactly, I think 250lbs per person and that includes luggage. A long history of weighing passengers and bags resulted in statistical averages plus a safety factor. If you got bumped with seats available, it was likely because performance, perhaps takeoff, but often landing limits resulted in weight restrictions.

Comment Re:amazing no ground scale or even strain gauges (Score 1) 366

I've flown both and I'm not aware of that feature. Not saying your wrong- just haven't heard of this. Wasn't on A320 either, flew them a lot. As for reduced thrust on takeoff, there are benefits to be gained. For example, the likelihood of turbine failure increases at higher thrust. Engine life is shortened by max thrust- has to do with sulfidation of the blades. Noise reduction (some airports levy fines like Orange County). Comfort. Also the fuel savings you mentioned, but not really such a big factor. That said, max thrust is required at least once every 30 days by certification, and sometimes the prudent pilot just wants the added performance for safety (wet runways, clutter, or just because ;)

Comment Re:amazing no ground scale or even strain gauges (Score 1) 366

There are variables other than weight that factor into the performance calculation: runway, flaps, CG, desired thrust reduction, atmospheric conditions. These things are variables programmed into the FMC during preflight by the pilot. While they could be automated onboard (most already are but externally), it is not likely there is an adequate return on the effort required to make it work.

Incidentally, the company I fly for has made significant effort to lessen the likelihood of this kind of error. Our performance is done by a centralized loadplanner and SCAP (Standardised Computerised Aircraft Performance) QANTAS apparently aren't using this. One feature alerts the pilots if they have requested data for a weight that is unexpected, but it still gives us the data. It essentially says "is this really what you wanted because I don't agree that is what you weigh."

Comment Re:Why do these data need to be entered manually? (Score 5, Informative) 366

As a unionized airline pilot, I can assure you that your statement is completely false. I'd suggest that you visit here: to get a better idea about the kinds of things that union has done to improve safety in the industry. Such as the following: science based duty limits, TCAS, Captains authority, security of the cockpit, hazardous cargo, safety reporting system, etc.

I suspect, sadly, that your bias against unions is an indicator that your mind is made up already.

Comment Re:Why do these data need to be entered manually? (Score 2) 366

Obtaining performance data requires knowing how many people and bags and where they are located, which runway is used, flap setting CG and weather data like pressure, winds and temperature. These factors, exclusive of the atmospheric conditions, are dictated by the humans operating the plane and while they could theoretically be automated, there likely isn't enough return on the invested effort to do so.

Comment Re:Data data everywhere and not a drop to think (Score 2) 366

To add to this and in regard to the model flown here, The -800 and-900 versions are stretched and have higher MTOG. The end result is since the landing gear are just as short, there is even less margin for error with tail strikes. This is true both for takeoff and landing and results in higher rotation speeds as well as higher approach speeds. In some cases, this results in weight restrictions due solely to the needed increased speeds.

Also of note regarding Vmcg, if Vr (reject) is lower than Vmcg, you're overweight for takeoff. Virtually never a factor for a modern aircraft.

Comment Re:Data data everywhere and not a drop to think (Score 1) 366

Once airborne, the FMC can do performance calculations. But not unless it has been given the variables that only the pilot or load planner can know. Among the variables inputted by the pilot are ZFW, CG, cost index, flap setting, thrust reduction, and takeoff profile.

ZFW and CG relate to how many people and bags and where they are located. Cost index and thrust reduction are mostly economic decisions. Flap setting is dictated by runway choice.

Comment Re:Data data everywhere and not a drop to think (Score 4, Informative) 366

As long as the device and software (the iPad and app in this case) has been vetted by the regulating agency, it is acceptable to use and may actually be required. I'm unsure of the interface to which you are referring, but takeoff performance calculations are not integrated into any large transport aircraft that I have ever flown. The FMC can only calculate data accurately if its given the correct inputs- stuff like ZFW, CG, flap setting, reduced thrust setting, etc. GIGO

At my airline, takeoff data calculations are centralized (acquired through datalink) rather than carried onboard, but still require those variables.

Comment Re:5% (Score 1) 366

Performance data normally has a safety buffer built in. However, a 10,000kg error is not a variable that would fall into the margin or error for performance. The primary goal of reduced thrust is to extend the life of the engine. A secondary goal is to reduce the likelihood of a turbine failure.

Comment Re:The thing about the "bombing ISIS positions"... (Score 1) 488

Not disagreeing with you entirely, but to expound on the concept of

Victory through Air-Power.

In the context of war in general, "air power" would indeed only be a part of what's necessary to achieving any victory- as you pointed out. But specific to how to deal with ISIS, "air power" is even less important, as this is a battle of ideology more than one of territory or geography. We cannot bomb the hate from their souls. Moreover, the souls are scattered across the globe anyway.

it's the infantry and armor who are going to finish this in the long run

I think that was tried and in fact shaped the issue as it stands now. Frankly, in hindsight it seems a complete failure to have destabilized the region allowing the deep seated sectarian conflicts the fuel and air to explode.

I personally would see another attempt to invade the region as folly. I think Arab nations should solve this problem: bringing down ISIS in the short term and eliminating radicalism at home in the long term. But they lack the will.

Comment Re:I'm all Afrin now (Score 2) 310

It is wrong, IMO, to describe it as addictive due to the connotations of that word.

I think your right. A more accurate description would be that one can become physically dependant on oxymetazoline as the rebound congestion becomes worse the more its used. Additionally, and perhaps worse, regular use can cause a host of unwanted side effects:

Comment Re:Socalim is organized psychopathy (Score 1) 399

Define "fair share" please.

I can tell you what its isn't. It isn't executives getting paid the current exorbitant salaries- nobody is worth that. And they rarely seem to answer for failure. And it isn't living on $40K-$60K annual income in the US right now either.

You two seem to be arguing your positions on the premise that socialism and capitalism lie at exclusive and opposite extremes. The two can coexist. We have social security and free market economy, but both are in need of change. Here's some numbers you requested: and and

I think they show it is getting harder out there for working stiffs. Would you agree executive salaries are out pacing worker gains?

Comment Re:Would YOU want a camera on you all day? (Score 1) 294

Would YOU want a camera on you all day?

No. But in fair disclosure, I'm an airline pilot. I already have enough of my actions recorded to determine the cause of any potential mishap. FDR data is now used to monitor compliance, albeit without the ability to render punishment- only to improve safety by analyzing trends on a system wide basis.

To balance the preventive threat and the privacy issue

I think the point of video in the cockpit (trains and planes) is to improve safety, not to audit compliance in an effort to terminate misbehaving employees. Even if compliance were not the objective, I would not support its use as its suggested benefits are vastly overrated and the potential for misuse is significant. I suspect train "FDR" data is already monitored in a fashion similar to airline FDRs though I don't know if that data is used to improve safety.

My mother is a fish. - William Faulkner