olasek
Pattern Altitude
Does anybody know example of a DME station not co-located with a VOR or LOC? Apparently in Europe they show up once in a while but I was wondering how it is in US?
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DME station without VOR?
- Thread starter olasek
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tonycondon
Gastons CRO (Chief Dinner Reservation Officer)
i know of 1 or 2 that are co-located with NDB stations
Areeda
Pattern Altitude
How would you use a dme without some sort of azimuth indicator? It seems to define a circle not a position.
I'm wondering, not suggesting it's not being done.
Joe
I'm wondering, not suggesting it's not being done.
Joe
You can do so; remember, DME simply shows the distance (slant range) to the DME station. They are almost always colocated with a VOR, LOC or TACAN, but are nonetheless a separate device.
One challenge of using a DME which is not colo'd with a VOR or LOC is figuring out how to tune it, and for that, you need to use a DME channeling table. I knew a guy (strange one) who flew to Canada, and we looked all this up because certain of his destinations had NDB/DME approaches. So, you see what the DME's channel is (on the plate), and tune the DME (or, its associated NAV radio) to the matching VOR/LOC frequency which, even though you are not even receiving a VOR/LOC signal, nonetheless pairs the DME to the right channel.
http://www.tpub.com/content/aviationandaccessories/TM-1-1510-225-10/css/TM-1-1510-225-10_491.htm
http://www.avweb.com/news/avionics/183230-1.html
http://www.hallikainen.org/FCC/FccRules/1997/87/475/section.pdf
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olasek
Pattern Altitude
Actually many older FMS units prefer to use DME-DME for position fixing (triangulation) over VOR-DME or VOR-VOR. DME-DME gives you the least computational error - of course GPS is even better but some old FMS are not yet GPS capable.
Everskyward
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Here's an NDB/DME approach but the NDB and the DME are in two separate locations.
http://204.108.4.16/d-tpp/0910/06513NDG6R.PDF
http://204.108.4.16/d-tpp/0910/06513NDG6R.PDF
olasek
Pattern Altitude
Yes, but TUS is a VOR-DME here, isn't it? I am looking for a DME not co-located with VOR or LOC.
olasek
Pattern Altitude
Super, thanks.
Steve
En-Route
The following NDB-DMEs are not co-located with a VOR or LOC
Alaska
AMF
AHT
ANV
HBT
BVK
LUR
EHM
DUT
GAM
OYN
ILI
AFE
AKW
KKA
ADK
AIX
OQK
PDN
SRI
DGG
SPY
OLT
TNC
TOG
Idaho
HLE
Minnesota
ULM
PQN
North Carolina
DIW
Alaska
AMF
AHT
ANV
HBT
BVK
LUR
EHM
DUT
GAM
OYN
ILI
AFE
AKW
KKA
ADK
AIX
OQK
PDN
SRI
DGG
SPY
OLT
TNC
TOG
Idaho
HLE
Minnesota
ULM
PQN
North Carolina
DIW
flyingcheesehead
Touchdown! Greaser!
There's one at MSP that's not co-located with either a VOR or an NDB. It's used for the approaches to 12R/30L and to define the Minneapolis Class B:
Attachments
Unbeliever
Pre-takeoff checklist
That's technically not triangulation, as triangulation is azimuth-azimuth (bearing-bearing) fixing, and not distance-distance fixing.
I don't think you can do DME-DME without some sort of INS, as the unit has to know witch of the 2 possible solutions to throw out. 1 DME gets you anywhere on a circle, 2 DMEs gets you on the two points where the circles intersect. DME-DME is probably used to reduce the error bars on the INS Kalman Filter.
--Carlos V.
roncachamp
Final Approach
CZF, Cape Romanzof Alaska.
roncachamp
Final Approach
Not really colocated with a localizer, not like they are with VOR-DME or a VORTAC, but pretty close by. In the attached image the localizer array is in the lower right, the DME antenna is the white cylinder on the orange pole at the corner of the checkered equipment shack.
Attachments
roncachamp
Final Approach
The chartmakers can make that challenge-free.
Attachments
roncachamp
Final Approach
No, it's a VORTAC.
gismo
Touchdown! Greaser!
For a long time the DME upon which the Minneapolis Class B was defined was co-located with one of the ILS antennas at the MSP airport. Several years ago they relocated the MSP VOR from a point about 16 nm NW of KMSP to the north side of the airport property and at that time the DME was relocated to the same spot.
Edit: I just checked and Steven is correct in that the DME that defines the MSP Class B boundaries is still located at (and is frequency paired with) the GS antenna for RWY 12.
Edit: I just checked and Steven is correct in that the DME that defines the MSP Class B boundaries is still located at (and is frequency paired with) the GS antenna for RWY 12.
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roncachamp
Final Approach
I-HKZ is the RWY 12R ILS/DME, the RWY 30L ILS/DME is I-MSP. Different localizers, same DME. Interesting that I-HKZ has the restriction, "DME unusable beyond 25 degrees right of course" while I-MSP has no restrictions and I-HKZ DME defines the Class B airspace.
sanchezpaulk
Filing Flight Plan
Actually rho/rho for range delta, not theta/theta for azimuth delta.
roncachamp
Final Approach
The accepted terms are theta-theta and rho-rho, respectively. Azimuth-distance is theta-rho.
Halloween carryover?
With a bit of logic you can throw out one of the solutions. Wait ten minutes or so and take the distances from the two DME sources again. You now have two displacements, since you know what your heading was one of them can be eliminated.
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gismo
Touchdown! Greaser!
That is weird. I wonder if the angular restriction on I-HKZ DME only applies inside the 6nm ring where the Class B goes to the ground (making the accuracy of the DME less important for defining the boundaries).
roncachamp
Final Approach
The Minneapolis VORTAC, MSP, was about 17 mile NNW of Minneapolis-St Paul International Airport, KMSP (aka Wold-Chamberlain Field). It was not moved, it was renamed Gopher VORTAC and redesignated GEP circa 1980. In the mid-eighties a new Minneapolis VORTAC, designated MSP, was established on the west side of the airport. The construction of runway 17/35 forced it to be relocated to the north side of the field as MSP VOR/DME
poadeleted20
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A third DME would also do, but I don't know which of the two methods FMS's use.
MauleSkinner
Touchdown! Greaser!
Interestingly (at least to me
) I shot those NDB approaches hundreds of times, but I haven't had the opportunity to fly them since they added the DME.I used a radial off FCM for my distance information--55 miles, almost perpendicular...1 degree is slightly under a mile, full deflection means I've probably passed the 10-mile limit for the procedure turn.
David
gprellwitz
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As an aside, what is inherent in your solution, but unstated, is that it requires altitude as an additional input into the solution.
Unbeliever
Pre-takeoff checklist
Which still sounds like you need some sort of Kalman Filter to remember and propagate vehicle state between the two measurments. Without an INS, that estimate is going to be sloppy. Still reinforces my statement that DME-DME alone doesn't get you position and you need some sort of vehicle state estimate to close the solution. Ron's suggestion of a 3rd DME also works.
--Carlos V.
Doggtyred
En-Route
There is one located on field at EFD (its a component of a standalone TACAN).. the terminal VOR component was decommissioned years ago.