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betelgeuse

DME?

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I know this is a bit of an old chestnut but previous threads here on this subject have not been too helpful.

 

I realise that in US many or most VOR/NDB approaches are now made with the GPS.  Thing is that this is not the case in many other parts of the world, notably GB and Europe.

 

If I am using a VOR approach plate which has timed approach descents on a VOR there seems no way to fly this accurately in the PC12.  Even with the GTN750 I cannot find a way to get a DME reading.  I just get the distance/time to the next waypoint.

 

Have I missed something obvious?

 

I'd be grateful for advice. 

 

John

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John

 

The DME  will display on the HSI. Bring up the pop up for the auto pilot which includes the controls for the HSI. You will see a button for both pointers. When you click on them they will allow you to select which nav aide they display. If you set nav 1 for pointer I, it will display the DME for nav 1 as well. If you select nav 2 for pointer II it will display the direction and DME for nav 2. In addition, the DME for an ILS set on Nav 1 will display ion the upper right portion of the HSI.

 

Greg

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+1 for Greg.

 

John, you mention timed descents... these do exist, but are normally used as back up when a DME is u/s or a DME doesn't exist. In that case you wouldn't get a DME reading if it doesn't exist. You have to fly the approach AT the noted speed (there's a box with varies speeds and times) and stay at that speed for descents and nail the timing (makes it difficult with wind, but generally much higher minimums).

Lindsey

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Thanks, Greg. I missed this.

 

Lindsey, to do a timed approach, I need to know where to start the approach as published on the approach plate. For that I usually need a distance reading.

 

If the beacon happens to be on the approach side of the runway there may be a published hold which will give the altitude at the point from where a timed descent can begin. Then I do not need a DME reading although it helps greatly to monitor the descent.

 

But, if the beacon is on the airfield or beyond, a distance reading is needed otherwise the pilot has no idea where to begin a timed descent.

 

That's my understanding anyways but I am a mere PPL.

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Hey John

No worries being a "mere PPL" you're willing to learn far more (in RL and here) than most desk jockeys flying around Vatsim :wink:.

 

For a timed approach you don't need DME, that's the whole point. "Generally" there will be an NDB BEFORE the rwy. You'd fly an outbound bearing to do the procedure turn, once established inbound descend to the published altitude. Once you cross the NDB AT the required approach speed start the clock, maintain that speed in the descent (remember you'll need to throttle back) till you reach the MDA level off, maintain bearing until missed approach time and or visual with rwy "environment".

 

Referencing a flight from CYVR (Vancouver) to CYCD airport NDB RWY 16 plate (can get off FLTPLAN.COM, free to sign up, AWESOME site with a fantastic iPad app). You could fly the G1 from VR NDB at 3,000' to YCD NDB(START YOUR TIME) then turn right to outbound bearing of 007 deg, desc to 2,500', make your procedure turn RIGHT within 10nm (how do you know if no DME, timing again! say Speed 130kts = 2.17 miles per min, so need to complete the turn and be back inbound within 5mins ish, hence start your time). Once established back on the inbound bearing of 187deg can desc down to 1,200'. Nail your approach speed again before reaching YCD (so maybe 110 now). Once crossing YCD [sTART TIME] left to outbound bearing to 162deg desc to 880' (recommended 600fpm min to be AT MDA BY the go around time, gives you more time to look) then at 2:08 at 110kts ( you can interpolate at 120kts to be 1:58 timing), you decide to land or go missed approach. Don't forget to make your radio calls! Starting approach, beacon outbound, procedure turn inbound, beacon inbound, down and clear or on missed approach.

 

Yes, it's  A LOT of work, but YES it's SO rewarding to nail it in IMC and POP comes the rwy. Just remember the NDB needle "push the head to the bearing or pull the tail" for correcting the bearing pointer; so if beacon inbound and the needle (head) is pointing to 172deg you need to steer like 182 deg to push it over to 162.

 

Wow, this makes me want to go shoot this approach now! Good luck!

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Live and learn.  Or maybe in RW, learn and live :wink:

 

Thanks for all that detail, airbmetravel.  You've got me curious now, so I'll have a try at the CVVR to CYCD NDB Rwy 16.

CAVOK first, then fog, then crosswind with fog etc. 

 

Should be fun! 

 

John

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VOR 1 and VOR 2 in Carenado PC-12

 

Though I have tried extensively, I am unable to point VOR 2 to a given radial/course.

Just to give an exemple: flying a DME ARC to Inverness EGPE (Great Britain) coming from GARVA. In a Cessna SP172, VOR 1 is pointed on 306° and VOR 2 on 54°, the final approach course.

 

Well I didn't find a way to do this though it should be possible.

Has anyone a clue?

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