IFR navigation

Amr Hosny

Amr Hosny

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Amr
Can we fly IFR without a GPS and if so how to reach the waypoints / fixes for an approach or a hold?
 
Lots of people fly IFR without GPS.
Lots of people flew IFR before GPS was invented.
In fact people flew IFR before electronic navigation equipment was invented. Maybe not always sucessfully, but they did.
Fixes and holds are defined points in space. The points are defined by distance and angle from a known location or by the intersection of two radio (vor) signals. For example, it's common to be given a hold instruction "hold north of X vor on the 45 radial". No GPS involved but the airplane must have navigation equipment that can received the VOR signal. Or the same instuction based on an NDB radio signal, aka AM radio.
 
Flying IFR without GPS, maybe for the unwashed masses :cheerswine:

But seriously, is this a real question?? Of course you can, plenty of planes were flying IFR before GPS..
 
James331 said:
Flying IFR without GPS, maybe for the unwashed masses :cheerswine:
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then there are hundreds is not thousands of aircraft and pilots that are in dire need of baths.
But seriously, is this a real question?? Of course you can, plenty of planes were flying IFR before GPS..
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James331 said:
Flying IFR without GPS, maybe for the unwashed masses :cheerswine:

But seriously, is this a real question?? Of course you can, plenty of planes were flying IFR before GPS..
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I'm asking how?
 
Amr Hosny said:
I'm asking how?
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See post #2. Essentially non-gps fixes are defined as a point on a VOR racial either a specific distance from the VOR (via DME), by the point the radial from an adjacent VOR or localizer crosses the airway radial, or both. For more info download the Instrument Fying Handbook from the FAA.
 
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tsts4 said:
See post #2. Essentially non-gps fixes are defined as a point on a VOR racial either a specific distance from the VOR (via DME), by the point the radial from an adjacent VOR or localizer crosses the airway radial, or both. For more info download the Instrument Fying Handbook from the FAA.
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So you need a DME with the VOR.
 
Amr Hosny said:
I'm asking how?
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VORs are radio beacons that have directional information embedded in the signal. The receivers in the aircraft decode the information and a pilot can determine the direction to/from the beacon.

If two VORs can be received at the same time then the aircraft location can be determined with some precision. Typically VORs are located such that finding an airport without looking out the window can be accomplished relatively easily by either flying directly to the airport or by intercepting a radio beam that is aligned with a runway.

Many folks have been rated for IFR without turning on a GPS. I am one of those folks.
 
Amr Hosny said:
So you need a DME with the VOR.
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Some sort of electronic navigation is required, that's what allowed the concept of IFR navigation. Back in the Dark Ages, around WW2, radio navigation was a radio signal issuing Morse code A and N that let you know which side of the approach to the runway you were on. Hence the clear and shaded graphics that still appear on some charts.

Agree with a recent poster to this thread, download the IFR manual from the FAA website and learn about the numerous IFR tchnologies, of which GPS is only one.
 
Clark1961 said:
VORs are radio beacons that have directional information embedded in the signal. The receivers in the aircraft decode the information and a pilot can determine the direction to/from the beacon.

If two VORs can be received at the same time then the aircraft location can be determined with some precision. Typically VORs are located such that finding an airport without looking out the window can be accomplished relatively easily by either flying directly to the airport or by intercepting a radio beam that is aligned with a runway.

Many folks have been rated for IFR without turning on a GPS. I am one of those folks.
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Flying a radial to and from a VOR, I'm familiar and comfortable with however if you are to make an approach by arriving at specific IAF, IF, FAf how can determine the distances for each one of those fixes. Is it still by determining the two radials of two VORs ( assuming you don't have a DME).
 
Clark1961 said:
A Piper Cub has no flaps and no electrical system so the answer is no.o_O
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No IFR in a nordo cub, but flaps are not required for IFR. Nav equipment is required, which means an electrical system.
 
Amr Hosny said:
Flying a radial to and from a VOR, I'm familiar and comfortable with however if you are to make an approach by arriving at specific IAF, IF, FAf how can determine the distances for each one of those fixes. Is it still by determining the two radials of two VORs ( assuming you don't have a DME).
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That's one way to do it. Station passage is another.

The approaches themselves indicate what the method allowed/required is.
 
Amr Hosny said:
Flying a radial to and from a VOR, I'm familiar and comfortable with however if you are to make an approach by arriving at specific IAF, IF, FAf how can determine the distances for each one of those fixes. Is it still by determining the two radials of two VORs ( assuming you don't have a DME).
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Intersecting radials are one method of determining a fix. Intersecting a localizer or passing over an NDB or marker is another method. Basically a fix is determined by following one defined radio path and intercepting another radio beacon/path. The passing of marker beacons while tracking a localizer used to be common fixes. Most of the middle and inner beacons are long gone.

And after you've passed a fix it can get real interesting trying to find the airport when all you have is a single radio signal, altimeter, and clock...
 
Without DME or an intersection you can rely on Time. See the lower right corner of this approach plate for an example.
 

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Amr Hosny said:
Flying a radial to and from a VOR, I'm familiar and comfortable with however if you are to make an approach by arriving at specific IAF, IF, FAf how can determine the distances for each one of those fixes. Is it still by determining the two radials of two VORs ( assuming you don't have a DME).
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It depends on the airport. Sometimes you will follow the localizer and determine distance by DME; sometimes only, and often as backup, you fly by airspeed and descend based upon time. The distances and times are published on the approach plate. The need to go Missed is determined by DME and / or time.
 
Amr Hosny said:
Flying a radial to and from a VOR, I'm familiar and comfortable with however if you are to make an approach by arriving at specific IAF, IF, FAf how can determine the distances for each one of those fixes. Is it still by determining the two radials of two VORs ( assuming you don't have a DME).
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Some approaches require either RADAR or DME for the transition from the enroute environment to the approach. If either is required for that purpose it is no notated on the approach plate.

Most approaches have the transition from the enroute environment on the approach plate. This could be a feeder route or a fix or navaid that is common to both. Fixes can be identified by an intersection of two VOR radials/NDB bearings, a LOC and radial/bearing/DME, or a DME on a radial/bearing. Any specific requirements for DME will be notated on the chart.

Enroute navigation is via airways or direct to navaids (within service volume limitations). RADAR vectors can also be used by ATC, or requested, in the enroute and terminal environment in most areas in the CONUS.

My initial instrument rating was completed in a 1960 C-310E which had two VOR receivers and one ADF but no DME. I spent more than a decade flying DC9s around North America with nothing more than two VOR receivers, two DME receivers, and one ADF.

For more detailed information I'd recommend the Instrument Flying Handbook, the Instrument Procedures Handbook, and the AIM. All available free online from the FAA web site.
 
ZeroPapaGolf said:
If your only contribution to the thread is to insult the OP, just leave it alone.
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I agree. This kind of comment is getting kind of old, especially since flying by GPS and iPad is becoming more of the norm rather than the exception.
 
Clark1961 said:
We use time to try to find the airport but never to define a fix.
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True enough. The time doesn't start ticking down until you get to the FAF. I was only pointing out that the stopwatch can substitute for DME on many (not all) VOR approaches.

Similarly, but completely off topic, a GPS can substitute for DME on approaches that are marked DME REQUIRED.
 
murphey said:
Lots of people fly IFR without GPS.
Lots of people flew IFR before GPS was invented.
In fact people flew IFR before electronic navigation equipment was invented...
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This fake news epidemic is now getting completely out of hand... :rolleyes: :D
 
GRG55 said:
This fake news epidemic is now getting completely out of hand... :rolleyes: :D
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I read somewhere that people fly without a flight plan on file. Can you believe it?

And for the pedantic - you could depart VFR without plan filed, and get a pop-up IFR clearance. Sometimes that's the fastest/easiest way.
 
Amr Hosny said:
Or two VORs
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Flew 12 years in the Army with no DME and single VOR. No auto pilot either. Uphill both ways. :D Seriously though it can be done and done to LIFR. It's all about VOR airways direct to either an NDB, ILS (OM) or GCA recovery.

Heck, you got F-18s flying around with no ILS, no IFR GPS and no iPad with FF...now that's scary! :eek:
 
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And they say there is no stupid question. This just disproves that theory.
 
Clark1961 said:
Your sense of humor is weak this morning...
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Forgive me, Obi Wan...I have done so little flying this year due to crappy but obscenely remunative employment, that my fun quotient is in the dumps. Gotta fix that.
 
murphey said:
In fact people flew IFR before electronic navigation equipment was invented. Maybe not always sucessfully, but they did.
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I was not aware of that, and I thought I was an expert in the history of IFR flying, starting with Jimmy Doolittle's first IFR flight and the Low Frequency Radio Range. Can you please elaborate?
 
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