What is Raw Data?

jwp_145

GhostRider in the Sky
I've heard a few people throw that term around when discussing navigation. What exactly does it mean?
 
I've heard a few people throw that term around when discussing navigation. What exactly does it mean?

Waay back before RNAV, GPS, integrated flight directors and autopilots, a primitive people used these means to navigate.

These indigenous people used basic attitude indicators in combination with a Direction Gyro, airspeed indicator, altimeter, and turn coordinator which were normally scattered about the panel in no particular order. To navigate they used airway markers, wearing a headset to hear a constant tone. As they would wander off course, they would hear dots or dashes indicating they were left or right of course.

As people evolved, a union called "ALPA" invented the "ALPA-T" or the "six pack", arranging the instruments in a logical, standard fashion based on rudimentary human factors training.

As time progressed, this became a standard for about 40 years. navigation went to DF (Direction finding - where you had to crank the antenna) to ADF (the antenna moved itself). Somewhere along the line, some inertial navigation equipment was invented (as the Germans weren't courteous enough to provide land based stations to aid our navigation). Then the VOR and ILS came along. You could track a course YOU selected off of a land based navigation system, and fly an approach that would end you looking at the runway. All with equipment you had in your cockpit, using ground based equipment maintained by the "Federal Government". We now know this as Slant Alpha.

Up until the mid-90s, about everything except the most advanced airplanes had no flight director, a six pack with a DG (unless you were lucky and had an HSI) and a wing leveling autopilot at best.

Then some computer nerd invented a way for this magical "glass" to integrate all the navigation features from boxes all over the panel that the pilot had to pick and choose which to use at the right time using a "scan" to get the pertinent information for that phase of flight.

As soon as glass became widespread and cheap, the devolution of the "raw data" flight set was complete, save some unsavvory characters known as "Freight Dawgs".

So now with our waning sense of history, occasionally pilots of glass filled flying machines will switch off the flight director (near emergency), the autopilot (Are you F'n spoofin' me?), switch the CDI from a GPS source to a ground based nav source and pretend they are over Ho Chi Minh city flying a C123 full of illicit arms to drop, while shooting a straight-in visual approach to ICT.


That my friend is raw data. :D






:yup::yup::yup::yup:
 
I've heard a few people throw that term around when discussing navigation. What exactly does it mean?

It means a lot of things, depending on who you talk to. As BobDDuck said, some people refer to flying with no flight director as "raw data", but I've usually heard it as displaying NAVAID information instead of (or in addition to) FMS or GPS information. I've also heard it refered to as displaying a GPS or FMS course needle or deviation bar, instead of flying off of a "stick map". But it's not like an official term or anything. You probably won't find an FAA approved definition for it.

In the KC-135, one of the 2 pilots was supposed to have a VOR needle displayed (at the very least). Ostensibly, this was supposed to be your backup in case one of the points in the FMS was entered incorrectly and the airplane went "tooling off into the weeds". Other guys thought that you needed at a minimum a VOR needle AND a DME readout displayed on one of the two cockpits, since a VOR needle alone doesn't fix a position (since you could be anywhere along the displayed radial). We refered to this as "displaying raw data".
 
In the KC-135, one of the 2 pilots was supposed to have a VOR needle displayed (at the very least). Ostensibly, this was supposed to be your backup in case one of the points in the FMS was entered incorrectly and the airplane went "tooling off into the weeds". Other guys thought that you needed at a minimum a VOR needle AND a DME readout displayed on one of the two cockpits, since a VOR needle alone doesn't fix a position (since you could be anywhere along the displayed radial). We refered to this as "displaying raw data".

Wouldn't "raw data" be the -135 pre-CRAG? :D
 
I see, so it's basically like flying instruments on gauges alone, say in a 172M model?
 
If anyone has ever been in an Initial or Recurrent for a type of some sort they have definitly done a Raw Data approach. It can be anything, VOR, ILS, but you cannot use the Flight Director for additional guidance.
 
Three methods of flying MOST large aircraft:

- "Raw Data"
- Flight Director
- Autopilot coupled with Flight Director

Although some operators disagree, I heavily side with operations manuals that strongly encourage proficiency in all three modes.


Raw data is also a lot easier to disseminate when shooting circling maneuvers (DCA runway 1 circle-to-land 33, etc).
 
Three methods of flying MOST large aircraft:

- "Raw Data"
- Flight Director
- Autopilot coupled with Flight Director

Although some operators disagree, I heavily side with operations manuals that strongly encourage proficiency in all three modes.


Raw data is also a lot easier to disseminate when shooting circling maneuvers (DCA runway 1 circle-to-land 33, etc).

If you are circling to land you should be using the wind screen as your navigational instrument.

Also flight directors are pink for a reason... on the EMB anyways.
 
If you are circling to land you should be using the wind screen as your navigational instrument.

Also flight directors are pink for a reason... on the EMB anyways.

Agree! I don't understand why some people make circling maneuvers out to be some sort of amazingly complex, precision maneuver that pits you on the edge of success or failure. It's simply a contact maneuver, a rough pattern flown lower than normal. Challenging? Can be. Dangerous? Not any different than flying a low VFR pattern.
 
If anyone has ever been in an Initial or Recurrent for a type of some sort they have definitly done a Raw Data approach. It can be anything, VOR, ILS, but you cannot use the Flight Director for additional guidance.

Everything in the E170 and 747-400 is Flight Director ON

Except steep turns and stalls.

AFAIK, the requirement is a "manually flown" approach from the PTS, which means no AP.
 
Agree! I don't understand why some people make circling maneuvers out to be some sort of amazingly complex, precision maneuver that pits you on the edge of success or failure. It's simply a contact maneuver, a rough pattern flown lower than normal. Challenging? Can be. Dangerous? Not any different than flying a low VFR pattern.

Some guys get so caught up in programming the FMS with crazy fixes and vertical guidance it's ridiculous.

"Be a pilot."
 
I've heard a few people throw that term around when discussing navigation. What exactly does it mean?

Depends where you are, and who your talking too. If your at work, being a true professional :), it means flying a ILS with no flight director.

If your in the bar with a flying buddy, off duty, and a pretty girl walks by, "I'd hit it, raw data!"
 
Some guys get so caught up in programming the FMS with crazy fixes and vertical guidance it's ridiculous.

"Be a pilot."


My entry for the Expressway Visual:

DIALS
DIALS085/RW31134
RW31

Put 2500 on DIALS and you are good to go.

That said, I DO fly the River Visual for 19 with out any snowflake.:)
 
That said, I DO fly the River Visual for 19 with out any snowflake.:)

I can appreciate someone who knows what they're doing and knows the limits of automation... I'm sure you know the type I'm talking about though. You know, the folks that accept crossing restrictions immediately without having the least bit of SA to realize that it would mandate a 6,000FPM descent. Or the type that is so heads-down in white needles that they poke through P-56.


Just for kicks, try these for the RVR VIS 19:

CABBN/3000
GLEYN/2100
CHAYN/1800
F332D/1200
MASSN/300


I personally fly both the Expressway and River Visual "raw," but that doesn't mean it can't be done a million different ways.
 
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