I just looked at the Aerocache of the day for April 15 (Kalohi-Pallolo Channels) and think there is a problem with the instructions. It states to fly the intersection of Lanai VOR on the 210 radial, the Maui VOR on the 88 radial, and the Molokai VOR 285 radial. VOR radials extend away from VOR on the magnetic course indicted by the number. Therefore, the stated radials do not intersect.

 

If the reciprocal of the given VOR radials is used, they do intersect. This would make the instruction state Lanai VOR 030 radial, Maui VOR on the 268 radial, and the Molokai VOR on the 105 radial.

 

Just a thought. I haven't finished flying it yet, but I think I have a better chance of finding the point with the adjusted numbers.

 

Happy flying,

GW

 

Sorry for the double post.

I noticed they were backwards as well, but it's still fun to see a radio nav cache!

I noticed they were backwards as well, but it's still fun to see a radio nav cache!

 

Yes, but I don't think it is funny they made such a huge mistake on this one...

I only tuned in one VOR, the Lanai VOR at 117.7 (worked fine as long as you stay on the 30/210 radial)

Oh yes, It's at about 5,000 feet, so don't be looking for it down by the water.

One of the more fun aerocache.

I just climed to 5,0000 feet, headed out between the two islands and there it was. Not very difficault. No need for a VOR intersect.

Hi,

 

Perhaps I read something wrong, or my understanding of radials is incorrect but I assumed that I would be at a point in space where the various VORs would be at the directions indicated. Referring to the map I estimated where that point was and when I started the hunt I noticed the standby frequency was set for Molokai so I just climbed to 5000 and got on that radial. Saw the aerocache in just a few minutes.

I hope someone knowledgeable clarifies this.

 

Jim F.

It can also be seen the other way around.

 

Think of it this way: If you were “standing” at the aerocache location, the given VOR radials are correct.

From that point you are at the intersection of inbound radials to MKK 285, LNY 210 and OGG 88

 

For those interested, see this sectional: http://skyvector.com...chart=38&zoom=8

Think of it this way: If you were “standing” at the aerocache location, the given VOR radials are correct.

From that point you are at the intersection of inbound radials to MKK 285, LNY 210 and OGG 88

 

Opening myself to criticism, yet again...

 

The radials do not dissect the VOR and pass through to the other side. They begin and go outwards from the VOR emitter. Let me clarify that there is a difference from the radial and the signal for that radial. The only time you can be "on" the 088 radial for OGG is if you are physically east of the transmitter. Then you are flying to or from the VOR station on the 088 radial. You can be physically west of the VOR station and tracking the 088 radial, but you are "on" the 268 radial when doing so.

 

Imagine the confusing that would occur by saying I'm on the 088 radial tracking inbound and having people try to decide if you are flying west at 268 and being physically east of the VOR or be physically west of the VOR and flying in a easterly direction. I would almost imagine that if I were flying east at 088 being west of the VOR and talking to ATC I might be told to contact the tower once I was on the ground...

 

 

An aside to Jeroen, this was brought up before, when I realized all three radials took me away from the planned target point.

Hi,

 

Even though, with the instructions provided, I knew where to find the Aerocache, it does seem that there is a problem with the phrasing. Can anyone suggest a better wording? And by better, I don't mean so lengthy as to eliminate any possible source of confusion know matter how ridiculous.

 

Jim F.

Imagine the confusing that would occur by saying I'm on the 088 radial tracking inbound and having people try to decide if you are flying west at 268 and being physically east of the VOR or be physically west of the VOR and flying in a easterly direction. I would almost imagine that if I were flying east at 088 being west of the VOR and talking to ATC I might be told to contact the tower once I was on the ground...

 

In that case you are supposed to indicated your current heading. To avoid the confusion, a common practice is to always use the same magnetic course as the VOR radial. Otherwise your VOR indicator would show FROM even when you are heading towards the station and you have to use reverse-sensing to keep on course.

The radials do not dissect the VOR and pass through to the other side. They begin and go outwards from the VOR emitter. Let me clarify that there is a difference from the radial and the signal for that radial. The only time you can be "on" the 088 radial for OGG is if you are physically east of the transmitter. Then you are flying to or from the VOR station on the 088 radial. You can be physically west of the VOR station and tracking the 088 radial, but you are "on" the 268 radial when doing so.

 

I know radials don’t dissect the VOR. The lines I drawed on the sectional were meant to indicate my position relative to each VOR, and what radial I would have to fly in order to “hit” or fly over each one.

 

If I took off from PHJH and wanted to hit the spot I would set my radios to inbound MKK 285 and LNY 210/OGG 88. (All 3 reading inbound radials)

 

Depending on the active RWY I would turn R or L to intercept the 285 radial to MKK and fly until I intercepted LNY 210, I could then activate the stand-by OGG and check if I was on its 88 radial.

 

My position at the Aerocache site would be ~24 nm ESE of MKK, ~16.4 nm NE of LNY and ~21 nm W of OGG.

 

Cheers.

If you take off from the recommended airport and set your VORs to the given directions, you'll hit the aerocache. My understanding of radials had all three being on the reciprical of the given directions, but it was easy enough to figure out. I just took off from Lanai and flew on the 30 radial with the Maui VOR set to 88 and waited for the Maui radial to center.

 

Hook

The phrasing problem is in the use of "radial." By FAA definition, A "radial" is defined as an orientation "FROM" the station. The Instrument Flying Handbook describes an example of an aircraft north of a VOR station heading south toward the station. This was described as flying an inbound course of 180 degrees on the 360 radial. The outbound course would be 360 degrees while on the 360 radial.

 

The instructions could have been stated correctly in several different ways; one to use the radials off the stations (as defined as the outbound directions), or to use other to use courses inbound or outbound from the station on intercept. In the last method, it is important to state whether the course is inbound or outbound relative to the station.

 

I'm not trying to start arguments by this, but to apply as much consistency as possible with real world flying. Many Flight users have never been exposed to VOR/VORTAC navigation, so the differences would not be apparent, and that is OK. And for some, just fetching the Aerocache reword is enough however it is achieved, and that's OK with me. But for me, my goal was to practice VOR navigation procedures, and in doing so properly, reach the achievement. I could have done this without saying anything, but was hoping to contributing to improving our Flight experience.

 

Where possible, I think we should encourage proper procedures and practices, and maybe help someone else learn a bit of airmanship. At any rate, lets have fun with Flight.

 

GW

Hi GW,

 

Any waffling on my part to your post wasn't due to my doubting its accuracy but my confusion. I too, noted a problem with the "Hint" but just didn't get around to identifying it.

To answer a question I posed, as to how the Hint could have eliminated the error, and in keeping with the terse Hint style I suggest:

"5,000 feet. 210 degrees to the Lanai VOR, 88 to Maui VOR, 285 to Molokai VOR.

 

Jim F.

"5,000 feet. 210 degrees to the Lanai VOR, 88 to Maui VOR, 285 to Molokai VOR.

 

Sounds perfect. Thanks.

 

Hook