# Tag Info

48

The zero reading is calibrated for main-wheel touchdown in a landing attitude. With the antenna forward of the main gear, it is, at that point, higher than it will be after the nosewheel is lowered to the runway. So to put some rough numbers to that, in the landing attitude, mains on the ground, the antenna is roughly 8 feet above the runway, but it reads 0 -...

41

The specific reason all-uppercase was adopted is just historical. Traditional steam gauge faces use capital lettering exclusively. The reason for that is that capital letters are easier to produce with limited tooling. When they were installed in aircraft, this cost-efficient convention was followed. This pattern is not exclusive to gauges: historically, in ...

25

In low light or with vision partially obscured (like, say, smoke), all caps can be seen from farther away and/or with greater clarity. This is more important than the easier to follow at a glance word-shapes you have with upper and lower case text, which is only a significant benefit when words are strung into sentences that you scan.

20

Initially, I would like to apologize for the not-so-good quality of the pictures (there were taken into a busy enviroment). I tried to find some vector photos from the respective manuals but I couldn't, that's why I took them by myself. I am going to provide you with some information on each photo. It is very synoptic description in order to get the help ...

16

Many aircraft do include them, because it's very useful. For example a modern 737: A Garmin G1000 (one of the more common General Aviation glass cockpits): Specifically the part that looks a bit like this And a more traditional analog/mechanical gauge: The problem is that usually when someone stalls, it's because they've made a mistake - not because ...

16

For at least certification under the FAA via AC 25-11B all upper case is acceptable but not explicitly required. If you're building an instrument and you know that all upper case will be accepted during certification it's only logical to build it that way. 5.4.2 Regardless of the font type, size, color, and background, text should be readable in all ...

15

On the Embraer 170/190-series, the normal display layout is as follows: There is an automatic display reversion logic when one or more panels fail. The following image shows this logic: There is also a manual reversion switch located near each pilot's outboard knee, which controls what is displayed on the panel: All images sourced from an Embraer Airplane ...

14

Yes there are standards. There are industry standards which not regulatory standards, but they have been deemed acceptable by the regulatory agencies (e.g. FAA). So following them is usually accepted without issue. The FAA also provides guidance in the form of an Advisory Circular, AC 25-11B Electronic Flight Displays. You have two separate things to ...

14

Slightly off-topic, but I recently came across the "side string" which gives a direct reading of AoA. Every gilder pilot is familiar with the yaw string, but in two years of learning to fly gliders, I'd never heard anyone mention the side string. Now, in the ultralight / open-cockpit world they use a single piece of yarn mounted on a stick, which acts as a ...

14

What you are describing is a Course Deviation Indicator or CDI. These are fairly standard across most aircraft however they may also be combined with a heading indicator resulting in an Horizontal Situation Indicator. There are also variants that have an aircraft symbol such as you describe. Depending on how your aircraft is setup these units can be ...

13

Synoptic refers to the active system diagrams that are selectable, usually on one of the middle displays above the center console. If you want to know what the hydraulic system is up to, you can select the Hydraulic Synoptic and an active diagram of the hydraulic system appears, showing what's pressurized and what's not, valves open and closed, the ...

9

The answer to the specific question of "why PFD's (glass cockpits) use this standard" is because their old style gauge cockpits used it before them. The glass cockpits of today are made to be similar to the older gauges so as to avoid confusion in their operation when moving from one type of aircraft to the other. This has been shown to be an issue in the ...

9

Oddly enough, I was able to find quite a few descriptions for the word, all of them defining synoptic as presenting a summary or a general view of something, and in my opinion, the meaning of the word is best described in Wiktionary by the etymology of the word: Ancient Greek συνοπτικός (sunoptikós, “seeing the whole together or at a glance”), from ...

9

These are engine vibration measurements. The image you show is the Compact Engine Display: 3 Vibration (VIB) Indications Displayed as digital readout only. (Boeing 737 NG FCOMv2 - 7.20.1 Engines, APU - Over/Under - Displays) The value comes either from the EEC (Electronic Engine Control) or the sensor directly: Oil pressure, oil temperature, oil ...

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 ...

8

It's a Heads Up Display, or HUD. The HUD can display a number of different pieces of information, including performance data such as airspeed, altitude, and attitude, navigation data such as waypoints or ILS glideslope, or weapons data such as the selected weapon or the targeting reticle you mentioned. Thus, its uses are varied - depending on how ...

8

If they used green (like grass) you would have asked the same: "Why didn't the use brown (like soil)?" Blue - brown is easier to distinguish, than blue - green, blue - red or another color-combination you can think of. Contrast: The use of this two colors can be explained by the high contrast from blue to brown. The pilot can find out with one quick glance ...

8

In the B737MAX, being a full glass cockpit, the light 'AOA Disagree' is indicated by an alert on the PFD (rather than a physical bulb). This is why Boeing was selling it as an option: it is just a software change to show or hide 'AOA Disagree'. Image taken from B737 MAX FCOM 10.10.33

7

That isn't a "three-dimensional radar display". It is a two-dimensional display with altitude encoded as color. Current ATC radar is two-dimensional, with altitude encoded as a number: A true Three-Dimensional Radar would look something like this: (Photo liberally thieved from a 1956 edition of Popular Electronics.) As far as 2D radar goes, I don't ...

7

It strongly depends on the aircraft we're talking about. As an example, this is the Head Up Display of an F/A-18 "Hornet": The number near the α is the angle of attack (AoA or α) measured in degrees. I presume that only in certain conditions knowing the exact value of the AoA may turn out to be useful (when nearing the limits maybe...). Usually, exceeding ...

7

Bear in mind that YOU may be comfortable with lower-case letters, but there are other cultures in the world that have different symbols for their alphabets, and they have to learn the Latin alphabet as something new. So having only upper-case letters makes it easier for non-Latin users. Note that this idea of all upper-case also applies to the QRH. For ...

6

They are nautical miles, which is the standard for essentially all discussions of distance in aviation. (Visibility being an exception; it can be reported in essentially every unit except nautical miles.) The software certainly could switch the display to another scale such as kilometers, although I’m not familiar with any systems that provide that option.

6

VSD Boeing have a patent on a VSD (Vertical Situation Display), which is part of the Honeywell EGPWS (Enhanced Ground Proximity Warning System) which first appeared as an option on 737s about twelve years ago I think. The system will be offered by early 2003 as a customer option on in-production 737s and by retrofit on 737-600/-700/-800/-900 airplanes ...

6

I have no true evidence that it is really related, but upper case only used to be the standard before the 80's. For example, METAR et TAF messages (meteorological observation and previsions on airports) used to be exchanged in old 5 bits Baudot code that can only represent upper case alphabets - and the code for both messages still only contains upper case ...

6

Yes, certainly there are standards for crew awareness messages. The number of messages displayed is normally limited by screen space allotted, which is may vary from around 5 to 15 messages and when there is a 'spillover' the messages continue on the next page. The pages are selectable via a simple cancel/recall push button and may also automatically change ...

6

Boeing 777 fuel-system display; A.Katranzhi, CC BY-SA 2.0, via Wikimedia Commons The following: 747-400 and 747-8 777 787 ... display aircraft systems digitally. Except the -400, they also have electronic checklists. For Boeing, it started with the 747-400. The main drive for it was customer demand. After which it was to be like the 757/767, but the "...

5

From the manual: So it appears that this instrument's terminology is a little non-standard. Additional information: From the Youtube video, you can see that they are moving at a fair pace: If you take these numbers and plug it into the equations from this question, $$Ram~Rise=SAT\times0.2\times{M}^2$$ (remembering that SAT needs to be in degrees Kelvin)...

5

OP asked what to do. If indicator becomes unaligned with roll pointer, apply more rudder on the side where the indicator has moved. It's called, "stepping on the ball." So if the slip/skid is right of the roll pointer, apply right rudder. If the indicator (a ball in the analog turn coordinator) is too far left, apply left rudder to force it back into ...

5

The slip/skid indicator is the small bar under the roll pointer. The image below should clarify that. Image from flightlearnings.com The Slip/Skid Indicator (sometimes called turn-and-bank indicator) moves left and right relative to the roll pointer in proportion to lateral acceleration and helps the pilot correct for any deviations in a turn. In a level ...

5

It’s a customer option (i.e. the operator can choose and specify) to switch between the two; presumably by pin programming the computer responsible for generating the display symbols.

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