DC-10 FMA -- Physical Design

[parkave231]

Hello, everyone -- I was hoping someone might be able to tell me about the physical design of the DC-10's flight mode annunciator, those four lights above the ADI.  In later years, readouts could use seven-segment LED displays (I'm thinking of the MD-80s) -- but based on the DC-10's design date and the very limited up-close pictures I can find, they certainly aren't segmented displays. Since the messages in each of the four indicators can change, it doesn't seem like it could be just a normal one bulb, on-off, display. And it certainly looks much too small to be anything CRT-based.


www.airliners.net/photo/Northwest-Airlines/McDonnell-Douglas-DC-10-30/842677/L

www.airliners.net/photo/Varig-Log/McDonnell-Douglas-DC-10-30-F/615599/L


To my completely amateur eye, they look more like IEE one-plane displays (or something similar -- that's just the only one I know), with some tiny lightbulbs and screen masks in the tiny display -- a smaller version of this:

www.decadecounter.com/vta/articleview.php?item=695

This would allow for multiple messages to be displayed based on different screen masks for each bulb, and you can also mix in plain colors with no masks, giving you yellow and green messages.  Put four small ones side-by-side, and...

But that's just a guess.  Does anyone know about the guts of the FMA and the technology inside that created the displays?

Thanks for any input!

Matt

[aerofoto - HJG Admin]

I was hoping someone might be able to tell me about the physical design of the DC-10's flight mode annunciator, those four lights above the ADI.

We refer to it as the Flight Mode Annunciator (for convenience of most peoples understanding) but its referred to as the "Flight Guidance System" .... in the R/W.

Those 4 lamps are part of the Flight Guidance System and work in relation to multiple AP and AT functions.

Myself and George compiled our DC-10 manual .... and what we represent within our panels, and the way it all functions, came straight a from a R/W DC-10 manual (supported by endless discussions with retired DC-10 FE's). I no longer have the manual as it was returned to the airline which provided it to us after we completed our DC-10 project and were satisfied everything was working authentically .... "as authentically as FS will enable such functionalities to be represented at least".

You can probably now acquire DC-10 manuals online (in PDF form) an quite inexpensively .... if you want to pursue your query more thoroughly

Does anyone know about the guts of the FMA and the technology inside that created the displays?

"THIS"/the following information (from our panel manual) might not be of any help to you "at all" in relation to your actual query and we've no information now in regard to the equipment or its foundation/s .... BUT .... what's presented below might be sufficient to allow you to draw your own conclusions at least .... assuming you may have adequate knowledge of the basics og it all

DC-10-10ER PANEL


CAPTAIN AUTO-PILOT MODE CONTROL PANEL (all DC-10 panel versions and duplicated to the FO panel too).


CAPTAIN MAIN PANEL - PRIMARY INSTRUMENTS (all DC-10 panel versions and duplicated to the FO panel too).


DC-10 PANEL FGS ANNUNCIATOR ("TEST" mode .... all DC-10 panel versions and duplicated to the FO panel too



3.01: DC-10 AUTOPILOT

The DC-10 AP instrumentation is located below the glare shield and is composed of the FD, AT, and all auto-flight related lateral and vertical navigation mode selectors.

Most FS panels feature push-buttons to select AP modes and which remain illuminated to indicate the selected mode. This is not the case using these DC-10 panels. The AP mode selector buttons illuminate only momentarily when depressed - with the selected mode then being displayed within the AP Mode Annunciator Panel on the Main Panel.

The DC-10 AP modes (except for Turbulence mode) cannot be cancelled by clicking on the relevant selector button a second time. Engaging an alternate mode will cancel a previously engaged mode (e.g. HDG and VOR/LOC).

In the case of AP ALT and HDG modes the target altitude and heading must be selected, then the "ALT" and "HDG" knobs depressed in order for the AP to be able to engage the selected modes. This action simulates the selector knob being pulled, a value set, and the selector knob then being reset in order for the selected values to be engaged by the AP.


AUTOPILOT MODE ANNUNCIATOR LIGHTS

Selected AP and AT modes are always displayed per the AP Mode Annunciator Panel located above the ADI gauges in both main panels. The function of each light (from the left-most light) is described below


LIGHT 1: AUTOTHROTTLE ANNUNCITOR.

- Light 1 within this annunciator indicates the autothrottle mode.

- "SPD": This is the most common AT mode used in flight with the system holding the selected target IAS. When the AT is engaged in flight it initializes in "SPD" mode and power is automatically adjusted in order for the selected airspeed to be acquired and maintained. If the AT is in "N1" mode (or "EPR" mode on the DC-10-40 panels only) then power will be automatically adjusted in accordance with a thrust rating consistent with the maximum thrust value displayed within the Thrust Limit Computer in order for the selected airspeed to be acquired and maintained.

- "ALPHA SPD": This is activated automatically when the selected target IAS is dangerously low given the simulation's weight and flap setting. When activated the minimum safe flying speed will be maintained. Once a safe airspeed is established (or airspeed becomes a safe due to increased flap deployment) the normal AT "SPD" mode will resume.

- "N1" (or "EPR" in the DC-10-40 panels only): When engaged power is automatically adjusted in accordance with a thrust rating consistent with the maximum thrust value displayed within the Thrust Limit Computer in order for the selected airspeed to be acquired and maintained. It can also be engaged by selecting the "N1" button located with the AT section on the AP panel, or by engaging TAKE OFF/GO AROUND mode using the "TOGA" button located below the thrust levers on the C/P sub panel.

- "CLAMP": Freezes the thrust levers in place. This initializes when engaging the AT while on the ground and when exceeding 80 KIAS during take off using "TOGA" mode.

- "RETD": Cuts the engine thrust to idle. This is only engaged during an autoland and whilst flaring for the actual landing.


LIGHT 2: ARM ANNUNCIATOR:

- Light 2 within this annunciator is for any mode that has been selected but has not yet been acquired.

- "LAND": Indicates that "LAND" mode has been engaged but the localizer and/or glide slope have not yet been intercepted.

- "VOR": Indicates that "VOR" mode has been engaged but the selected radial has not yet been intercepted.

- "ILS": Indicates that "ILS" mode has been engaged but the localizer and/or glide slope have not yet been intercepted.

- "LOC": Indicates that "LOC" mode has been engaged but the localizer has not yet been intercepted.

- "B/CRS": Indicates that "BACK COURSE" mode has been selected but the ILS localizer has not yet been intercepted.

- "ALT": Indicates that a target altitude has been selected but not yet acquired. This indication can also be combined with "LAND, VOR, ILS, LOC" or "B/CRS" indications.

Light 2 of this annunciator also indicates the status of the Autoland system once the simulation is established on an ILS approach ....

- "APP ONLY": Indicates that both ILS localizer and glide slope are both intercepted with autopilot in ILS mode only (no autoland mode).

- "SNGL LAND": Indicates that the ILS localizer and glide slope are both intercepted with autopilot in "LAND" mode (autoland mode) and with only one autopilot engaged. This is permissible for any CAT 1 type approach (decision height >= 100 feet AGL, visibility > 1,000 feet).

- "DUAL LAND": Indicates that the ILS localizer and glide slope are both intercepted with autopilot in "LAND" mode (autoland mode) and with both autopilots engaged. This is permissible for any CAT 2A type approach (decision height >= 50 feet AGL, visibility > 600 feet).


LIGHT 3: ROLL ANNUNCIATOR

- "CWS": Indicates that the bank angle can be controlled manually (up to a maximum limit of 35° left or right) - except when the controls are released and at which point the current bank angle is then maintained by the AP (unless the bank angle is less than 3° and in which case the wings will be levelled automatically).

- "HDG SEL": Indicates that the simulation is turning towards the selected heading displayed in the AP HDG window.

- "HDG HOLD": Indicates that the AP is holding the simulation's current heading.

- "INS CAP": Indicates that the simulation is manoeuvring onto a track programmed into the INS.

- "INS TRK": Indicates that the simulation is following a track programmed into the INS (in reality the DC-10 has a separate INS driving each AP but in these simulations the second INS is replaced by the default FS2004/FSX GPS).

"GPS TRK": Indicates that the simulation is following a programmed GPS route.

"VOR CAP": Indicates that the simulation is manoeuvring onto the selected VOR radial.

"VOR TRK": Indicates that the simulation has intercepted the selected VOR radial.

"LOC CAP": Indicates that the simulation is manoeuvring onto the selected ILS localizer.

"LOC TRK": Indicates that the simulation has intercepted the selected ILS localizer.

"B/CRS AP": Indicates that the FD is guiding the simulation's manoeuvring onto an ILS localizer back course.

"B/CRS TRK": Indicates that the FD is guiding the simulation during an ILS localizer back course intercept.

"ALIGN": Indicates that the simulation is being aligned with the runway prior to touchdown during an automatic landing.

"ROLLOUT": Indicates the simulation is following the runway centre-line after touchdown while also lowering/derotating the nose during rollout after landing rollout.

"G/A": Indicates that the FD is guiding a Go Around manoeuvre after the "TOGA" button has been engaged in flight – the actual go-around must be flown manually.

"TAKE OFF": Indicates that the FD is guiding the take-off after the "TOGA" button has been engaged on the ground – the actual take-off must be performed manually.


LIGHT 4: PITCH ANNUNCIATOR

"VERT SPD": Indicates that the simulation is maintaining the vertical speed as selected using the VS thumb wheel within the AP sub-panel.

"ALT CAP": Indicates that the simulation is within 100 FT of any selected target altitude and is levelling off.

"ALT HOLD": Indicates that the simulation has acquired the selected target altitude.

"IAS HOLD": Indicates that the AP is using pitch attitude to maintain the airspeed acquired when "IAS HOLD" mode was first engaged. This mode cannot be selected if the AT is engaged in either "SPD" or "ALPHA SPD" mode.

"MACH HOLD": Indicates that the AP is using pitch attitude to maintain the velocity acquired when "MACH HOLD" mode was first engaged. This mode cannot be selected if the AT is engaged in either "SPD" or "ALPHA SPD" mode.

"GS CAP": Indicates that the glide slope has been intercepted and the simulation is manoeuvring in order to capture the glide path.

"GS TRK": Indicates that the simulation has intercepted the ILS glide slope.

"FLARE": Indicates that the AL system is raising the nose to commence the flare for touchdown/landing.

"TURB": Indicates that "TURBULANCE mode is engaged. This functions similarly to "CWS" mode except that the AP is less precise in regard to maintaining the selected attitude.

"G/A": Indicates that the FD is guiding a Go Around manoeuvre after the "TOGA" button has been engaged in flight – the actual go-around must be flown manually.

"TAKE OFF": Indicates that the FD is guiding take-off after the "TOGA" button has been engaged while on the ground – the actual take-off must be performed manually.

"CWS": Indicates that the pitch is being manually controlled (up to a limit of 18° left or right bank) - except when the controls are released and at which point the current pitch attitude is then maintained by the AP.


DUAL AUTOMATIC LANDING

A CAT 3A automatic landing requires (for safety reasons) that not only two separate AP's are used but also that no single failure can simultaneously render both AP's unusable. For this reason it is required that all AC buses be isolated. This occurs automatically when both AP's are engaged and the appropriate generators are available, and is indicated by the AC Bus Isolation lights (blue) - in contrast with the AC Bus Isolation lights (amber) which illuminate when AC buses are manually isolated, or are unable to be connected due to being out-of-phase with each other, or because the GPU is powering the AC Tie bus.

The "DUAL LAND SELECTED" light (blue) illuminates when both AP's are engaged for any automatic landing.

If the #1 and #3 engine-driven generators are engaged and running both AP's will also illuminate the "DUAL LAND PWR ON" light (green) - as well as the AC Bus Isolation lights (blue) - indicating that the simulation is correctly configured for a dual automatic landing. If one or both of these generators is not running then these lights will remain extinguished and it will only be possible to land using a single AP. This scenario will be indicated by the AP MAP displaying "SNGL LAND" rather than "DUAL LAND" indications when the ILS Localizer and Glide Slope are captured, and which means only a CAT 2 approach and landing may be performed.

Mark C
AKL/NZ

[parkave231]

Cheers, Mark -- I do always enjoy your insights. Looking back through the manual, I'm not sure that even my idea of the one-plane display would work, as there would probably need to be more bulbs than are probably possible for the number of different messages and available space. You're right that the technical specs are probably buried deep in a DC-10 manual somewhere.

One of the YouTube channels I follow often posts videos of different types of displays from the 1950s through the 1980s, well before things like LED and LCD displays made all sorts of new thing possible. One day while flying the DC-10 the question just popped into my head!

Matt

[aerofoto - HJG Admin]

I'm not sure that even my idea of the one-plane display would work

YEP .... that's a fair comment

I think it's also probably fair to say that because the DC-10 remained in production over some 20 years, the "type of systems" (meaning system/s vintage and/or version .... and not not just in regard to the FGS) likely changed/evolved within this period and to the extent that later production aircraft, and models, likely featured progressively more modern variations of the original FGS equipment .... or were possibly upgraded accordingly.

Probably the most major DC-10 FD and systems upgrade was when some DC-10-10CF/F's and DC-10-30CF/F's (FED EX operated aircraft primarily) were upgraded with MD-11 type EFIS systems (these upgraded DC-10's were then rebranded as MD-10-10F and MD-10-30F aircraft) .... and which also dispensed with the FE as a 2-crew FD then became standard.

In the case of the DC-10 panels were offer here the AP and AT related systems represented within each are identical and function identically too .... whilst each of these aircraft type specific panels also feature different instrument standards (in regard to engine related gauges) and FE sub panel layouts too. In regard to these latter features we wanted to try'n represent the panels of each aircraft type/version as authentically as possible .... rather than taking "the lazy route" and just slopping together a re-hash of precisely the same panel for use with everything. The differences among the DC-10 panels we offer are all presented, and well explained, within our following-linked forum based DC-10 manual ....


DC-10 PANEL MANUAL
tonymadgehjg.proboards.com/thread/9147/dc10-panel-installation-handling-notes


What we offer does tend make for "a slightly more complex" project, but, it does also ultimately make for "a far better and more authentic project too". If some people find the panels we offer are too complex for their liking .... then .... they can easily replace the standard/active FDE suit (bot AIR and CFG data) which accompanies each of our DC-10 base packs with our "NO-HJG PANEL" version FDE (contained within a base pack sub-folder by that same name) and use this data with another simpler panel .... but in doing so people also then need to appreciate we can't provide support for them/for someone else's panel

Mark C
AKL/NZ