Search found 81 matches

  • 1
  • 2
by Trimeresurus
Sun Nov 22, 2020 7:55 am
Forum: Technical/Operations
Topic: The "windy" sound coming from 737NG after takeoff
Replies: 2
Views: 615

The "windy" sound coming from 737NG after takeoff

You can hear in the 3:44 in this video: https://youtu.be/R1dS-ZqG_Ps

Is it the wind flowing around the retracting landing gears? It's a weird sound only heard in the 737, just like the barking HYD pump of A320

Jump to post
by Trimeresurus
Wed Nov 18, 2020 9:50 am
Forum: Technical/Operations
Topic: Why did HUDs come to airliners so late?
Replies: 27
Views: 3047

Re: Why did HUDs come to airliners so late?

With a HUD, the hand-flying pilot can easily fly as or more precisely as the autopilot. It’s an order of magnitude more precise than heads down. And, it simplifies visual flight, makes night visual “dark hole” approaches a piece of cake, and the transition from cloud to visual reference automatic. ...

Jump to post
by Trimeresurus
Mon Nov 16, 2020 9:01 pm
Forum: Technical/Operations
Topic: Workload of the PNF in the 732
Replies: 17
Views: 1529

Re: Workload of the PNF in the 732

Why did the 727 have a flight engineer then? With wide bodies I think it was a FAA requirement.(though I don't imagine 747 classic being that different to operate than 737 Jurassic other than the taxiing part and maybe the flare) But 727 was light enough to bypass that requirement?

Jump to post
by Trimeresurus
Sun Nov 15, 2020 11:09 am
Forum: Technical/Operations
Topic: Workload of the PNF in the 732
Replies: 17
Views: 1529

Workload of the PNF in the 732

As we all know, the Boeing 737 Jurassic was a two man cockpit in an era which three was standard for the pressurized, fast and high flying planes. This was before FADEC, EEC, automatic cabin pressure control, EICAS, electronic control of buses, and most importantly, FMS performance calculations. So ...

Jump to post
by Trimeresurus
Sat Nov 14, 2020 2:32 am
Forum: Technical/Operations
Topic: Why can't flight data and CVR record be sent to the ground stations continuously by satellite and/or VHF?
Replies: 50
Views: 2635

Re: Why can't flight data and CVR record be sent to the ground stations continuously by satellite and/or VHF?

It would be very possible and no reason it can't be done.The question has been answered extensively on this forum. Try to use the search function for further info. Short version: The amount of data has grown heavily and and bandwith is expensive. Further, CVR data are highly sensitive and personal ...

Jump to post
by Trimeresurus
Fri Nov 13, 2020 8:11 pm
Forum: Technical/Operations
Topic: Why can't flight data and CVR record be sent to the ground stations continuously by satellite and/or VHF?
Replies: 50
Views: 2635

Why can't flight data and CVR record be sent to the ground stations continuously by satellite and/or VHF?

Is the tech still not there yet? Considering how far we've come with 5G and stuff, it's interesting that we still have to hunt for black boxes under ocean if the unthinkable happens. And considering that we have internet(albeit slow) on newer wide bodies now, and the fact that drones can be remotely...

Jump to post
by Trimeresurus
Wed Nov 11, 2020 10:38 pm
Forum: Technical/Operations
Topic: What is the last airliner produced with cable hydraulics instead of FBW?
Replies: 4
Views: 1430

What is the last airliner produced with cable hydraulics instead of FBW?

Is it the 737NG? I guess last one rolled out in 2019, and they still make BBJ versions.

Jump to post
by Trimeresurus
Tue Nov 10, 2020 8:03 pm
Forum: Technical/Operations
Topic: Where is the engine run-up area on LAX located?
Replies: 5
Views: 1383

Where is the engine run-up area on LAX located?

The Rules&Regulations on lawa.org says it's located North of taxiways A and C, yet despite looking at the FAA diagram, Jeppessen taxi charts and Google Maps satellite view, I can't see a place where an engine run-up test would be conducted, especially not where LAWA says. Do they use the long ta...

Jump to post
by Trimeresurus
Mon Nov 09, 2020 8:26 pm
Forum: Technical/Operations
Topic: 777x vs 787
Replies: 9
Views: 2133

777x vs 787

Does the 777x employ the composite body, very flexible wingtips(not sure what they're called), bleedless system as well as other features such as electronic window dimming and whatnot? Or is it more like a legacy 777(I know MAX has a more similar build to the 737NG than the state of art 787)? I know...

Jump to post
by Trimeresurus
Mon Nov 09, 2020 8:22 am
Forum: Technical/Operations
Topic: How much less thrust does a modern high bypass turbofan engine generates at cruise altitude as opposed to sea level?
Replies: 25
Views: 2727

Re: How much less thrust does a modern high bypass turbofan engine generates at cruise altitude as opposed to sea level?

I suggest you start thinking in terms of air density at altitude (& don't forget the temperature!), and then consider Newton's 3rd Law. Ball park figure from memory.... a CF6 rated at 50,000 lb (static) take-off thrust might only produce 11,000 lb thrust at 40,000 feet at temperature X, and at ...

Jump to post
by Trimeresurus
Mon Nov 09, 2020 8:12 am
Forum: Technical/Operations
Topic: How much less thrust does a modern high bypass turbofan engine generates at cruise altitude as opposed to sea level?
Replies: 25
Views: 2727

Re: How much less thrust does a modern high bypass turbofan engine generates at cruise altitude as opposed to sea level?

It is very dependent on bypass ratio. A GE90-115B will have a bigger thrust lapse than a JT8D. The main reason for this is the fact that the closer you get to your exhaust speed in relation to your forward speed (in the atmosphere) the less thrust you create. Since turbojets and low bypass turbofan...

Jump to post
by Trimeresurus
Sun Nov 08, 2020 9:34 pm
Forum: Technical/Operations
Topic: How much less thrust does a modern high bypass turbofan engine generates at cruise altitude as opposed to sea level?
Replies: 25
Views: 2727

How much less thrust does a modern high bypass turbofan engine generates at cruise altitude as opposed to sea level?

Due to air being thinner at such altitudes, RPMs being equal, less air will be pushed away to generate thrust. Another factor to decrease thrust might be that there's less oxygen available for combustion, hence taking away a bit of vitality from the engine, though I'd think that'd be an issue mostly...

Jump to post
by Trimeresurus
Sat Nov 07, 2020 10:32 am
Forum: Technical/Operations
Topic: How does the ATC keep such precise seperations between aircraft during approach?
Replies: 44
Views: 3408

How does the ATC keep such precise seperations between aircraft during approach?

In some airports, most notably the IST, you can see several aircraft lined up to the same runway to land, seperated by maybe only 5-8NM and 1000-1300 feet in altitude. How does ATC balance the arrivals so close within each other? If say, the aircraft behind gets too close to one in front, is it inst...

Jump to post
by Trimeresurus
Fri Nov 06, 2020 7:10 pm
Forum: Technical/Operations
Topic: What's the procedure for runway incursion after the touchdown?
Replies: 12
Views: 1829

What's the procedure for runway incursion after the touchdown?

What is the pilot expected to do if after he touches down and slows down to a speed that's below what'd allow a safe re-rotation and go around(maybe 120 kts or less) and another aircraft/ground vehicle/person/animal whatever enters the runway and is on the aircraft's path? Do you just accept your fa...

Jump to post
by Trimeresurus
Thu Nov 05, 2020 4:47 pm
Forum: Technical/Operations
Topic: How do follow me vehicles avoid running into planes or getting affected by their jet blast on taxiways in very low vis?
Replies: 12
Views: 1666

Re: How do follow me vehicles avoid running into planes or getting affected by their jet blast on taxiways in very low v

At some airports the ground vehicles have some sort of Ads-b transponder. I’d be taxiing around and see airport operations vehicles driving around. I’d look on my iPad and see the ground vehicles on the taxi chart and their call sign as well. I thought it was kind of neat seeing the conga line of s...

Jump to post
by Trimeresurus
Wed Nov 04, 2020 1:51 am
Forum: Technical/Operations
Topic: How do follow me vehicles avoid running into planes or getting affected by their jet blast on taxiways in very low vis?
Replies: 12
Views: 1666

How do follow me vehicles avoid running into planes or getting affected by their jet blast on taxiways in very low vis?

Character count exceeded the maximum limit, so it was going to be "How do follow me vehicles avoid running into planes or getting affected by their jet blast on taxiways in very low visibility conditions?" I know some airports have ground radars but I doubt the guys in the follow me car ca...

Jump to post
by Trimeresurus
Tue Nov 03, 2020 6:23 pm
Forum: Technical/Operations
Topic: Before primary flight displays, where were their contents displayed?
Replies: 17
Views: 1846

Before primary flight displays, where were their contents displayed?

The attitude, speed and altitude obviously had their own analog indicators since forever, but what about stall speed, overspeed, AoA, flap speeds, pitch limitations, autopilot modes, flight director etc? For example, a 747 classic vs the 747-400.

Jump to post
by Trimeresurus
Sun Nov 01, 2020 9:22 pm
Forum: Technical/Operations
Topic: Question about ground personnel
Replies: 18
Views: 1574

Re: Question about ground personnel

Do ground personnel have interchangeable roles or do they strictly have one job? For example, do air marshallers ever handle cargo or plug in GPUs to aircraft? If marshaling aircraft is the only job that an aircraft marshaller does, and if so, doesn't it mean that majority of his day is spent doing...

Jump to post
by Trimeresurus
Sun Nov 01, 2020 9:22 pm
Forum: Technical/Operations
Topic: Question about ground personnel
Replies: 18
Views: 1574

Re: Question about ground personnel

Around here it depends on the airline and station as well. At our airline main bases with several airplanes coming and going we have dedicated ramp agents, cargo agents, cabin servicing agents, and passenger service agents, and at outstations where we often only have one or two flights pass through...

Jump to post
by Trimeresurus
Sat Oct 31, 2020 4:50 pm
Forum: Technical/Operations
Topic: Question about ground personnel
Replies: 18
Views: 1574

Re: Question about ground personnel

NWAESC wrote:
I'm a ramp agent in the US. At my airline, we do pretty much everything but fix, fuel, or fly them.


How did you decide to and become one if that's not too personal?

Jump to post
by Trimeresurus
Sat Oct 31, 2020 3:58 pm
Forum: Technical/Operations
Topic: Question about ground personnel
Replies: 18
Views: 1574

Re: Question about ground personnel

At least in the US, a dispatcher requires a FAA certificate and ramp agent does not. The ramp agent marshalls and pushes airplanes, connects and disconnects ground power and ground air, loads and unloads baggage and cargo, cleans the airplane cabin and lavatories, empties the waste tanks and refill...

Jump to post
by Trimeresurus
Sat Oct 31, 2020 12:18 pm
Forum: Technical/Operations
Topic: Question about ground personnel
Replies: 18
Views: 1574

Re: Question about ground personnel

I'm not sure about that. However I believe the cargo guys handle cargo. Marshallers, they can still be needed with a docking guidance system. For example, at TPE the ground traffic "road" is outside the bays, between the taxiway and the parking position. Marshallers are needed to stop tra...

Jump to post
by Trimeresurus
Sat Oct 31, 2020 9:05 am
Forum: Technical/Operations
Topic: Question about ground personnel
Replies: 18
Views: 1574

Question about ground personnel

Do ground personnel have interchangeable roles or do they strictly have one job? For example, do air marshallers ever handle cargo or plug in GPUs to aircraft? If marshaling aircraft is the only job that an aircraft marshaller does, and if so, doesn't it mean that majority of his day is spent doing ...

Jump to post
by Trimeresurus
Fri Oct 30, 2020 2:39 pm
Forum: Technical/Operations
Topic: Why did HUDs come to airliners so late?
Replies: 27
Views: 3047

Why did HUDs come to airliners so late?

Despite being standard equipment on fighters and some military transport aircraft since the 1970s, they seem to only have become standard in airline flying by 787/A350 generation(one exception is the 737NG, though HUD adoption in that wasn't very widespread).

Jump to post
by Trimeresurus
Thu Oct 29, 2020 4:19 pm
Forum: Technical/Operations
Topic: Who flies aircraft to storage areas?
Replies: 8
Views: 1368

Who flies aircraft to storage areas?

Is it usually the pilots of the airline, or does the storage area operator sends crew to pick up the aircraft?

Jump to post
by Trimeresurus
Thu Oct 29, 2020 2:05 pm
Forum: Technical/Operations
Topic: Pilots of airliners with yokes(Boeing/MD/Embraer/CRJ etc), do you keep your hands on the yoke during autopilot?
Replies: 9
Views: 1438

Pilots of airliners with yokes(Boeing/MD/Embraer/CRJ etc), do you keep your hands on the yoke during autopilot?

If so, when do you start to touch the yoke(I assume during cruise you let it be)? Below 10.000 AGL? 5.000? How do you make sure A/P doesn't disengage because it sensed a pressure on it? Also in FBW aircraft like the 777, why does the yoke move during autopilot if it's not connected to flight surface...

Jump to post
by Trimeresurus
Wed Oct 28, 2020 10:29 pm
Forum: Technical/Operations
Topic: Are cargo doors of passenger aircraft operated from the outside?
Replies: 11
Views: 2287

Are cargo doors of passenger aircraft operated from the outside?

Do they have a switch that the ground crew use to open them? Can it be overridden from the cockpit? What are the conditions necessary for the cargo doors to be available to open?

Jump to post
by Trimeresurus
Tue Oct 27, 2020 12:08 pm
Forum: Technical/Operations
Topic: How often is the full thrust reverse used vs idle?
Replies: 24
Views: 2324

How often is the full thrust reverse used vs idle?

I notice idle reverse is much more common nowadays due to less fuel burn and wear, but what are some conditions that justify a full(or near) N1 reverse thrust, other than emergency operations and rejected takeoff? Are they common for wet runways or high tailwind landings for example?

Jump to post
by Trimeresurus
Sat Oct 24, 2020 11:22 am
Forum: Travel, Polls & Preferences
Topic: Why did KLM replace the Boeing 747-400 on AMS-SXM route with an Airbus A330-300 and not a Boeing 777-300ER?
Replies: 24
Views: 3627

Re: Why did KLM replace the Boeing 747-400 on AMS-SXM route with an Airbus A330-300 and not a Boeing 777-300ER?

[twoid][/twoid]

mozart wrote:
Travel demand to St Maarten collapsed after the big destructions in the 2018 hurricane season. It never came back to previous levels, so less capacity was needed


But the replacement came in 2016?

Jump to post
by Trimeresurus
Sat Oct 17, 2020 9:22 pm
Forum: Technical/Operations
Topic: How can turboprops like C-130 and A400M cruise at the same height and speed as jets?
Replies: 34
Views: 4862

Re: How can turboprops like C-130 and A400M cruise at the same height and speed as jets?

Height - no problem. Speed is another matter. But higher an airplane gets, lower the density of the air it'll be in that flight level, so higher the stall speed(TAS) will be. Isn't this the main limitation regarding service ceiling of aircraft? Their cruise speed won't be even enough to generate li...

Jump to post
by Trimeresurus
Sat Oct 17, 2020 1:36 pm
Forum: Technical/Operations
Topic: How can turboprops like C-130 and A400M cruise at the same height and speed as jets?
Replies: 34
Views: 4862

How can turboprops like C-130 and A400M cruise at the same height and speed as jets?

How are propellers that effective at such thin air of FL300+? What stops something like the Caravan or the King Air(other than pressurization for the people on board) reaching that heights and speeds? And why do the militaries prefer props over jets, considering how popular C-130 is and the size of ...

Jump to post
by Trimeresurus
Fri Oct 16, 2020 5:51 pm
Forum: Technical/Operations
Topic: When does it become safe to approach an engine after shutoff?
Replies: 15
Views: 2703

Re: When does it become safe to approach an engine after shutoff?

But doesn't the flight deck crew wait for the engine to spin down before turning off the beacons? The last two airlines I worked with did. In a strong wind the fan wasn't slowing down much and they were waiting to turn off the beacons, and we were waiting for them!! Here is part of the shutdown che...

Jump to post
by Trimeresurus
Fri Oct 16, 2020 1:06 pm
Forum: Technical/Operations
Topic: When does it become safe to approach an engine after shutoff?
Replies: 15
Views: 2703

Re: When does it become safe to approach an engine after shutoff?

Yeah I meant, close enough to be able to touch the fan, not touch it. As in, right in front of the inlet, no distance from it.

Jump to post
by Trimeresurus
Thu Oct 15, 2020 6:28 pm
Forum: Technical/Operations
Topic: When does it become safe to approach an engine after shutoff?
Replies: 15
Views: 2703

When does it become safe to approach an engine after shutoff?

By approach, I mean as to get close enough to touch it's fans. Let's take a GE90, I assume after shutting off the engines at the gate upon arrival, beacons are also immediately switched off, but ground crew doesn't get close to the engines immediately since they have other duties to attend before th...

Jump to post
by Trimeresurus
Mon Oct 12, 2020 5:27 pm
Forum: Technical/Operations
Topic: Why did Boeing go from 5 screens to 4 screens in new designs?
Replies: 18
Views: 2626

Why did Boeing go from 5 screens to 4 screens in new designs?

Originally the Boeing glass would have two PFDs, two NDs, and and EICAS(or master caution, whatever). In the newer designs however, it seems like they crammed the engine and navigation displays to a single screen of pilot monitoring, and the pilot flying has one large navigation display that doesn't...

Jump to post
by Trimeresurus
Mon Oct 12, 2020 2:48 pm
Forum: Travel, Polls & Preferences
Topic: ATPs, how many of you studied engineering before becoming an airline pilot? S it common?
Replies: 0
Views: 611

ATPs, how many of you studied engineering before becoming an airline pilot? S it common?

Is it common? Did it allow you to understand the dynamics and systems of aircraft better and more intuitively? Do cadet programs prefer engineering graduates or is it entirely irrelevant?

Jump to post
by Trimeresurus
Sun Oct 11, 2020 8:31 pm
Forum: Technical/Operations
Topic: Are Airbuses really that much more automated than their Boeing counterparts made in the same year, or is it overstated?
Replies: 13
Views: 2895

Are Airbuses really that much more automated than their Boeing counterparts made in the same year, or is it overstated?

Maybe it's a bit more apparent in A320 vs 737NG comparison since 737 is antiquated, and there are outdated practices like manually choosing where to source your electricity or pneumatics from(engine vs APU etc) or no autostart, but those are just tiny details and a split second flicking of switches,...

Jump to post
by Trimeresurus
Sun Oct 04, 2020 12:56 pm
Forum: Civil Aviation
Topic: Demographics of GA aircraft owners
Replies: 43
Views: 6830

Re: Demographics of GA aircraft owners

jreeves96 wrote:
During my time as a line service technician, there's one demographic when it comes to personally owned GA planes ; 40+ year old white men.


I rather asked about the financial/occupation demographics but thanks for the input.

Jump to post
by Trimeresurus
Sun Oct 04, 2020 12:51 pm
Forum: Technical/Operations
Topic: In your airline, do you start the APU upon landing?
Replies: 23
Views: 3803

In your airline, do you start the APU upon landing?

Or do you wait for the ground crew to connect the ground power and/or the air cart(how often are air carts used anyway, for air conditioning)? If you do, and wait for the ground power, how long does it take for you to shut off the engine(s) after docking is completed? Also the the port for external ...

Jump to post
by Trimeresurus
Fri Oct 02, 2020 2:02 pm
Forum: Technical/Operations
Topic: During the crew shifts in long haul flights, how long does it take?
Replies: 25
Views: 4228

Re: During the crew shifts in long haul flights, how long does it take?

Some airlines hire most new joiners as cruise pilots, so they are the least senior pilots, and will eventually upgrade. At some airlines you can choose to remain a cruise pilot. At other airlines, especially if they have no narrowbodies, there is no option to remain a cruise pilot. Do any pilots ac...

Jump to post
by Trimeresurus
Fri Oct 02, 2020 1:52 pm
Forum: Civil Aviation
Topic: Demographics of GA aircraft owners
Replies: 43
Views: 6830

Re: Demographics of GA aircraft owners

Considering their price tag, which for example is well north of $300k for a Cessna 172 for a brand new one, they're not a viable hobby for the average middle class person, at least for ownership. How would you define an average owner of Cessna or a Piper, as in their occupation and experience in av...

Jump to post
by Trimeresurus
Thu Oct 01, 2020 8:19 pm
Forum: Civil Aviation
Topic: Demographics of GA aircraft owners
Replies: 43
Views: 6830

Demographics of GA aircraft owners

Considering their price tag, which for example is well north of $300k for a Cessna 172 for a brand new one, they're not a viable hobby for the average middle class person, at least for ownership. How would you define an average owner of Cessna or a Piper, as in their occupation and experience in avi...

Jump to post
by Trimeresurus
Fri Sep 25, 2020 3:13 pm
Forum: Technical/Operations
Topic: Navigation in an old six-pack airliner
Replies: 27
Views: 3124

Navigation in an old six-pack airliner

In the old days, like in 1970 when the first 747s started their Transatlantic flights for Pan Am, how was the main method of navigation? Was it primarily using ground beacons with the CDI and then heading vectors from ATC at lower altitudes/approaches? What about Transalantic routes, which is out of...

Jump to post
by Trimeresurus
Fri Sep 25, 2020 2:58 pm
Forum: Technical/Operations
Topic: How much non-voice(text) communication with the ATC is performed
Replies: 6
Views: 2218

How much non-voice(text) communication with the ATC is performed

Like with the ACARS Pre-Departure Clearance or maybe SATCOM, any environment that you can possibly communicate with the ground via the CDU. I know those are usually reserved for communication with dispatchers and maintenance/technical department, but is it for example common to talk with the tower i...

Jump to post
by Trimeresurus
Thu Sep 24, 2020 7:55 pm
Forum: Technical/Operations
Topic: What happens if you don't stab trim an aircraft
Replies: 11
Views: 2110

Re: What happens if you don't stab trim an aircraft

You can fly and land just fine with neutral trim. It just causes wear on the control surface attach points and is less efficient due to more drag. Hydraulic flight surfaces are always powered at 3000 psi, only the flow changes when moving them. I guessed that too, but I somehow thought prolonged un...

Jump to post
by Trimeresurus
Thu Sep 24, 2020 7:03 pm
Forum: Technical/Operations
Topic: What happens if you don't stab trim an aircraft
Replies: 11
Views: 2110

What happens if you don't stab trim an aircraft

Let's say you always keep the stab trim in neutral and keep your pitch by just putting pressure on the yoke, never once using trimming(or autopilot induced trimming) during whole flight, including final approach and flare, say in a 737 Classic or NG. Would the hydraulic system have issues because it...

Jump to post
by Trimeresurus
Wed Sep 23, 2020 11:03 am
Forum: Technical/Operations
Topic: Commonality between the 737 Original and 737NG?
Replies: 29
Views: 4965

Re: Commonality between the 737 Original and 737NG?

Presentation, e.g. the instruments, can change, but the systems themselves can't change too much or a new type certificate is needed. Are the 747 classic and -400/-8 under the same type certificate? I heard they're pretty different aircraft systemwise, that's why the -300s couldn't be retrofitted a...

Jump to post
  • 1
  • 2