Questions tagged [dme]
DME (Distance Measuring Equipment) is, as the name suggests, a system for measuring the slant distance between a suitably-equipped aircraft and a ground-based transponder station; DME stations are often colocated with VOR or ILS installations.
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How can the A320 receive 3 DME signals if it has only 2 DME receivers?
How can the A320 receive simultaneously 3 DME signals (VOR1 + VOR2 + ILS) if it has only 2 DME receivers (and antennas)?
Does it multiplex them in some way? If yes, does it mean if one DME receiver ...
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Are there two navaids on the same frequency close enough to be confused?
Several RTCA DO standards require checks for bad navaid tuning including, "In lieu of using ground-based navigation aid designated operational coverage (DOC), the system should provide, checks ...
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"w/o DME" minimums on DME required approach
I've found this ILS-Y 26 EPBY approach, where there are two LOC minimums: With D3.0 and w/o D3.0 on Jeppesen chart. On the original AIP charts it says "When stepdown fix not received", but ...
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How can I triangulate a position using two DMEs?
What is the formula for determining an aircraft's position (latitude, longitude) using barometric altitude and the ranges to two DMEs?
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How does an airborne DME unit differentiate itself?
The FAA's IFR handbook glosses over a keypoint:
The aircraft DME transmits interrogating radio frequency (RF) pulses, which are received by the DME antenna at the ground facility. The signal ...
user14897
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Difference between VOR approach (with DME required) and VOR DME approach?
VOR-A approach into KSFY
VOR/DME-A approach into 57C
These are two random examples of approaches I found that appear identical in the way they'd be flown and their setup. The first at KSFY is titled ...
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Are there benefits in training instrument students how to fly a DME arc?
With more instrument approach procedures being designed for RNAV/GPS equipped aircraft, and considering the high level of radar coverage currently available, is there a need to spend valuable training ...
user22445
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What does a DME indicator do in HOLD or RNAV mode?
I found this DME indicator on the Cessna 210. Its mode switch has four positions - NAV1, NAV2, RNAV and HOLD. NAV1 and 2 are clear - it uses the NAV1 and 2 freq respectively. I'm wondering what the ...
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How do you calculate the deviation from an RNAV waypoint radial?
As a clarification at the beginning: I'm talking about non-GPS, pure VOR-DME based RNAV devices here.
On RNAV devices that use just the selected VOR-DME, not GPS, the phantom radio station is set up ...
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Why don't aircraft have DME that can automatically convert the slant range to ground range?
Knowing that $a^2 = b^2 + c^2$ where $a = \text{slant range},\ b= \text{ground range},\ c = \text{height}$.
Why can't the DME equipment which calculates the slant range then just convert it to the ...
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What point are these distances from?
I am kind of confused with this approach and I come up with multiple questions.
First, in the profile view, the FAF is depicted 3.1 NM away and MAPt is depicted 0.6 NM away. My understanding is these ...
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Timing not authorized for defining the MAPt
Does anyone know why some charts have written "Timing not authorized for defining the MAPt"?
Could this happen when the DME required is written on the chart?
Thank you,
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What are the modulation parameters of a DME?
I am having difficulties finding specific information about DME pulse pair modulation. As far as I understand, the gaussian shaped pulse pairs are modulated using amplitude modulation. The carrier ...
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is DME groundspeed slightly inaccurate due to slant range?
When DME is calculating aircraft ground speed, is it doing it based off of the slant range? Wouldn't this mean that if the aircraft is at sea level and the DME is at sea level that the GS would be ...
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How does increasing the rate of pulse pairs in DME 'search' mode help?
From How does an airborne DME unit differentiate itself?
The higher rate in SEARCH [150 PP/S] gives it more opportunity to detect the replies as it has no knowledge of range in search and thus has to ...
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