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31

Short answer Aeronautical data (fixes, waypoints, navaids, instrument procedures) are delivered to aircraft operators and avionics manufacturers referenced to the WGS-84 ellipsoid. To make is simple the ellipsoid is the volume enclosed by the revolution of an ellipse which best approximates the shape of the Earth, generally in a given region only. WGS ...


17

The EMB-145 used a combination of FADEC settings and the thrust levers to select the desired thrust and to signify the need for additional thrust. The thrust levers had a detent that selected "100%" thrust for the given mode the FADEC is operating in. If you pushed the thrust levers past the detent to "max" this would give you extra thrust. The mode the ...


15

Having it explained to me briefly what exactly the tower does that cannot be handled by such a system would probably enlighten me somewhat. Fair warning, that's my job you're trying to replace with a computer, so I'm probably biased. Still though, hear me out: What do we do? Handle a large amount of non-standard requests and communication between the ...


12

The 'clip' is obviously a fake. Standards for avionics software development and testing are rigorous, with development of flight critical software being done by separate (independent) groups and legally required to be reviewed by another (independent) group. After that testing is done by another group/person who's certified by the regulatory authority. It ...


12

That's part of the High Altitude Redesign (HAR) program. As far as the available information, it's now available for flights above FL390, and only in certain ARTCC's in the U.S. The waypoint naming convention is as follows: There are plans to have this system implemented worldwide. The pilot will no longer be limited by airways based on ground navaids. I....


11

(Own work) The FMC is part of the FMS. The FMC is a computer system that uses a large data base to allow routes to be pre-programmed and fed into the system by means of a data loader. The FMS encompasses: The Flight Management Computer (FMC) The Automatic Flight Control or Automatic Flight Guidance System (AFCS or AFGS) The Aircraft Navigation ...


10

If the arrival is missing: If the departure is missing: And here are the affected items: Source: 787 FCOM.


9

Short answer: it's coming soon. For why can't they, the answer is limited data transfers at the moment, which is being worked on. See: How can shifting to TCP/IP make current aviation systems more delay-tolerant? Once implemented, it will be like the current CPDLC, where an instruction awaits the crew to press accept, reject, or cancel. A plane like the ...


8

Previous waypoints are not shown on the 787's CDU, and only the last waypoint or PPOS (present position at which a direct-to was initiated) shows on the ND. The 787 EFB does not show the plane position. Only very recently the FAA allowed own-ship display on moving maps. As to why, there is no use for it. The POS REPORT page on the 787 would show the three ...


7

Historically, avionics manufacturers have used off-the-shelf processors on custom circuit cards. Processor selection has been based on getting a reliable processor (established history) at a reasonable price and an expectation that it will be available for a long time. The high turnover (obsolescence) in processor design along with a lack of design ...


7

caseys answer nicely describes the procedure for the Embraer 145. Since you specifically mentioned the Boeing 737 and Airbus A320, here is how it works for these aircraft: Boeing 737 All Boeing aircraft have autothrottles with servo motors which move the thrust levers in the cockpit. This system is also used to set takeoff thrust: During the preflight, ...


7

Usually power output for a jet engine is gauged from its low pressure turbine speed. In turbofans, this corresponds to the fan speed, displayed as N1. In general, the derated takeoff thrust will be selected based on performance calculations done prior to flight, taking into account weight, runway available, climb performance and ambient atmospherics, which ...


7

Fuel bias is as you described it. As the engine ages, it burns more fuel than a brand new one. The fuel flow (and drag) corrections are entered into the FMS. This would allow the FMS calculated quantity not to disagree with the tanks totalizer. The figures are based off previous flights and engine tests. Maintenance personnel can refine the database by ...


7

The FMS Bridge Visual Approach 28R is a version of the Quiet Bridge Visual Approach 28R which is coded with GPS coordinates and can be included in an FMS database for approved operators. This allows the procedure to be used when the SFO VOR is out of service, and also gives ATC additional flexibility by allowing them to clear pilots direct to any of the ...


7

"we are all used to the QWERTY or QWERTZ layout..." or AZERTY. But which one? Universally there is no one standard, so whichever of these 3 (and others) is chosen, it will be wrong for some users. So the only standard left is simple alphabetic. Another thing to consider is that the QWERTY-types of layout were chosen to deliberately slow down typists on ...


7

In Boeing terminology, the FMS, Flight Management System, is comprised of: Flight Management Computer System (FMCS, which is essentially two FMC's, at least on the 737... other jets may have one FMC, or three) Autopilot AFDS (Autopilot/Flight Director System - includes the Mode Control Panel used to select autopilot modes, heading, speed, altitude, etc) ...


6

According to the Jeppeson chart legend[pdf] those are database identifiers. I'm presuming that's what would show on a menu in the FMS.


6

(Source) Whether the FMS is capable or not of calculating the V-speeds, it should be checked and may be overridden. It is because the airplane database wouldn't know if there's a temporary crane that will affect the climb limit weight, or if 400 ft of the runway are unusable due to maintenance, for example. In other words, 10,000' corrected-length runways ...


6

Since you are studying maintenance, I would suggest you obtain a copy of ATA iSpec 2200, Information Standards for Aviation Maintenance ATA Standard Numbering System. Most large aircraft manufacturers and airlines use the ATA Standard Numbering System in organizing their maintenance documentation. To your specific question, the ATA spec lists the ...


6

It's probably fake but there's no reason why it couldn't be in and why it couldn't be approved like that. An (The!) acceptable means of compliance to FAR/CS 23/25.1309 is DO-178. Airborne software is developed to meet a Design Assurance Level (DAL) which is derived from the aircraft level Functional Hazard Analysis and Preliminary System Safety Assessment (...


6

Turns out indeed it's an issue affecting polar operations. It differs from type to type, but for the 737-600/-700/-800/-900 as an example, the message UNABLE REQD NAV PERF-RNP will be displayed. For oceanic areas this will only happen if ANP shifts by over 10 NM, i.e., after losing the RNP-10 capability. At an IRS drift rate of 650 metres per hour, it ...


6

From the FCOMv2 4.10.10 (emphasis mine): Altitude Intervention (ALT INTV) Switch [Option - With speed and altitude intervention] Allows manual deletion of next FMC altitude constraint via altitude SEL and ALT INTV switch. Push – (during VNAV climb) lowest FMC altitude constraint below selected MCP altitude is deleted if airplane ...


6

Digital ATC communicating (digitally via data-link) directly to the plane's FMS is in theory doable. The problem is 2-part: Automating the repetitive tasks. The communicating. The second part (communicating) must come first, and once it is achieved, the future is limitless. This part has been troublesome since the late 80s. In short, who is going to pay ...


5

Some autopilots found on advanced aircraft can be engaged on selected axis only, for example Boeing 737, 747-200 & MD-11. There are three autopilot indicators on the Boeing autopilots: auto throttle, roll and pitch. Each can be in a different mode. Here a Boeing 737's autopilot roll mode is set to Heading Select (HDG SEL) while the Pitch is flown ...


5

Updating a navigation database used to be considered preventative maintenance and was required to be performed by a mechanic under Part 135. However, the regulations were changed at the end of 2012 (here is the final rule) and it no longer falls under this category so pilots are allowed to update "aeronautical databases" (a new term) if it is "easy" to do (...


5

F speed is the minimum speed at which flaps should be retracted from CONF 3 or 2 to CONF 1+F. S speed is the minimum slats retraction speed, i.e. the minimum speed at which a clean configuration should be selected. GD speed is the engine-out operating speed in clean configuration. In other words, it corresponds to the speed that allows the highest ...


5

If you are thinking of the analog of installing windows or linux on a given physical personal computer then the answer is more or less no. Not because its not possible but more because thats not how avionics are made or how the avionics pipeline has developed over the years. Avionics also work quite differently than your basic home computer as they are ...


5

Chapter 4 of Degani's Taming HAL covers some of the details of this disaster, and is on a NASA site The Crash of Korean Air Lines Flight 007 It details some of the interface deficiencies in the aircraft's navigation selection system. We don't have definitive evidence about exactly what happened, but it is possible. It goes over the idea that it was easy ...


4

By definition an FMC / FMCS is linked to the auto flight system. The closest thing to a standalone device is an EFB, but when it comes to fuel burn, and air data parameters, it's unable to compute the complex parameters since it's not connected to the air data computer and engines. I've checked the history. From a 1985 Sperry ad: Since the mid-1970s, ...


4

I assume that by updating you mean loading a pre-compiled database into the FMS, replacing the old one. The RNAV database inside the FMS should be updated according to the 28 day Aeronautical Information Regulation and Control (AIRAC) cycle. Typically this is a maintenance task and the pilot has no play in this. Of course if the pilot also holds the ...


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