Time markers not recommended?

[foxy]

cfi....

 

why are we raa teaching 1 in 60...rubbish???

 

really??

 

as far as im aware, the ability to fix your position on the map is extremely important...obviously...but when the winds arent as predicted and you have a low time nav student, who does end up off course...wouldnt you think it prudent to teach them how to get themselves back on course??

 

in my opinion, id rather see a dude use the 1 in 60 course correction method, than i would to see them having to use the 'lost' procedure...and/or having to call up radar to have them guide you back home...

 

honestly, lets face the facts...if ya get lost cos ya dont know how to get yourself back on course, it wouldnt take too long for some people to get a little flustered, and get lost. man...i say bring on the 1 in 60.

 

 

[Mazda]

CFI, I don't know what planet you are on, but the GA schools I know teach markers (10 mile, 6 minute - either will do) and this is expected at PPL and CPL level. It means diversions can be made at any time, not from a feature (there may not be a feature, it's not like Tasmania), and it ensures people are not "track crawling" from one landmark to the next.

 

Anyone track crawling will fail a CPL test, and track corrections must be made using a method, such as a 1 in 60, not by guesswork.

 

By the way CFI, military pilots are taught to navigate with minute markers, in fast aircraft they use 2 minute markers. They learn to navigate jets with a compass, stopwatch and map just like the rest of us.

 

Anyone who says it doesn't work because the wind changes hasn't been taught correctly.

 

 

[Mazda]

How so CFI? I don't understand why military and RA pilots are so interesting? I didn't mention RA, I was talking about GA and military.

 

Do tell why it is so interesting ...

 

 

[motzartmerv]

Did you not read the section in the CASA instructor flight manual?? Or are you just ignoring black and white facts?...

 

Whats interesting, is.......never mind.....

 

 

[Mazda]

OK CFI, maybe I'm being a bit narrow-minded. I'd like to hear your method of navigation and track correction, I might learn something.

 

Say I'm navigating Tibooburra, Corner Store, Nappa Merrie (Dig Tree), Innamincka, Arkaroola, Muloorina. In my little beast, no navaids. Maybe back via Broken Hill and Parkes.

 

 

[Mazda]

No sextant either.

 

 

[foxy]

of course ya wud cfi....as would i... but are you telling me that you have never altered off course...ever?? even by a mile if the winds werent right as predicted?? id still rather my dude be able to fix something if it was wrong...then just let it keep going. so if you find that you are in fact off course cfi....wot do you do to get back on course??? im guessing there has been a time that you have used the 1 in 60 rule...im also guessing that it worked. im pretty sure that if we didnt teach the 1 in 60, thered be some nasty situations that instructors teaching navs would have to answer for.

 

 

[Mazda]

Exactly CFI! So you've been flying over the Strezlecki for quite some time, how do you find where you are on the map?

 

 

[motzartmerv]

You pinpoint yourself on the map Mazda. If you look close, you will see a little picture of your aeroplane, and there you are....

 

No, seriously, any 1 in 60 is done using a pinpoint anyway, the argument, is, well, not an argument at all. I too am very interested to know how one navigates without a clock, and without a 1 in 60....

 

CFI, no comment on the GA instructor manual??..put out by CASA,??...as in, the governing body for GENERAL AVIATION (as well as the rest of us). , here, ill add it again...

 

ENROUTE NAVIGATION

 

It must be stressed to the student that after the compass

 

the aeroplane’s clock (or a watch) is navigationally the

 

most important instrument, as the time factor is vital in

 

fixing a position. With a knowledge of the flight planned

 

time intervals between check points, regular reference to

 

a time piece will provide an approximate but continuous

 

indication of the aeroplane’s position, the value of which is

 

sometimes overlooked by the student when too intent on

 

map reading. In essence the normal emphasis is on time,

 

then map followed by ground.

 

 

[Mazda]

Now CFI, that's a bit forward offering me your bed! :ah_oh:

 

I've flown in Tassie CFI, down to Melaleuca, into Sandfly etc. It's not very big!

 

Whip out your trusty Broken Hill and Cooper Creek WACs and let me know which line on the Strezlecki you will use, because believe it or not, those dunes actually shift!!

 

 

[flying dog]

I don't have time to read all the posts either.

 

Here is my "two cents worth".

 

And: Ok, I still haven't got my head around the 1/60 rule.

 

People learn things because they use them often in their daily routines. By repeatedly doing the same thing it becomes familiar and so you understand what is happening when you see the "problem" presented to you.

 

Time, speed and distance are all inter-related.

 

Speed is GROUND speed - ofcourse.

 

So knowing two of these you can determin the other one no worries.

 

Learing the maths to do this is done with repetition and doing LOTS of examples where you are given situations and you need to "crunch the numbers".

 

But looking at their "real" values, speed is not quite as simple as its name imples.

 

Speed is varied by the wind and heading, so it is not that easily quantified.

 

You draw you track on the map and mark 10 mile markers. Irrispective of you speed you time how long it takes to get between known points on the ground. This determins your speed.

 

"Problem" with this is you need to be always looking out the cockpit, searching for these points.

 

Irrispective of you speed these points stay fixed. So they can be used for all flights.

 

If you mark 6 minute markers and your ground speed is different to what you calculated, the points are void.

 

When flying the track, every 6 minutes you look out and get a "fix" on where you are.

 

"Problem" with this is, if you ground speed is different to what you calculated, you won't be where you thought you would be.

 

So when you look out the window and see where you are then you have to mentally find where you are. Then you have to find where you are on the map.

 

Ok, there is a bit of "mental trickery" there but to me it is double work load. But: We are all different. Some do it one way, some do it another.

 

I think distance is better as they are FIXED points. 6 minute markers are speed dependant, and so can't be trusted.

 

But that is just my thoughts.

 

Happy and safe flying.

 

 

[antzx6r]

Hi, just a quick note on 6 min marks. The confusion hear is that the 6min marks are placed on your map at planning stage. You don't set the stopwatch and at 6mins look out the window and see where you are. Not very accurate and just too hard. You track to the first mark and check your time to get there. It actually took 7 mins...? ok now your original 6min marks are infact 7 min marks. change your times and you have an updated eta. simple. thats what i was led to believe. Someone correct me if i'm wrong. Oh and on the subject of time, this is the most important part. Time gives your fuel consumption. You find that your eta blows out to an unacceptable time based on your fuel reserves then you must divert. I can't see the argument. You either make it or you don't. (with reserve of coarse)

 

 

[Guest davidh10]

I was taught, like, and use 10nm markers measured back from the destination (waypoint). In addition, elapsed times to each waypoint are calculated based on forecast winds and a multi-timer used to count down the time to run. On reaching a waypoint, you can adjust your times by dead reckoning, or if the timer has run out and you haven't found the waypoint, and you didn't have a greater than expected head wind, then lost procedures. (The timer continues below zero and shows as a negative time to run).

 

Ground speed can be read off the GPS, but in the event that you aren't using one or it fails, then it is easy to simply fly a constant rate 360 degree circle and observe ground drift, from which you can estimate wind strength and direction. The same manoeuvre with a GPS and watching ground speed and IAS will allow you to estimate wind speed and direction. You could also just measure time between two navigation reference points or map features or the 10nm marks to calculate ground speed and the component of wind speed opposing your track is the difference between ground speed and IAS.

 

If people want to use time marks and that works for them. Great, but you will notice that time also comes into the method I use. Time and distance are both important.

 

 

[pudestcon]

I was taught, like, and use 10nm markers measured back from the destination (waypoint). In addition, elapsed times to each waypoint are calculated based on forecast winds and a multi-timer used to count down the time to run. On reaching a waypoint, you can adjust your times by dead reckoning, or if the timer has run out and you haven't found the waypoint, and you didn't have a greater than expected head wind, then lost procedures. (The timer continues below zero and shows as a negative time to run).Ground speed can be read off the GPS, but in the event that you aren't using one or it fails, then it is easy to simply fly a 360 degree circle and watch the IAS and compass, from which you can estimate wind strength and direction. You could also just measure time between two navigation reference points or map features or the 10nm marks.

 

If people want to use time marks and that works for them. Great, but you will notice that time also comes into the method I use. Time and distance are both important.

I agree. I was taught the 10nm method and it works particularly well for me because I like the idea of calculating everything from a known constant. I work in the building industry where all levels and measurements come from a datum point (known constant) so maybe that is why the 10nm method works so well for me. But you need the clock as others have said - time and distance will give you enough to work out where you are and all else flows from that.

 

Pud

 

 

[motzartmerv]

Haha, so it was, my bad. Apologies for quoting the wrong dude.Im all for a good time and a joke, but this is the students thread, not the place to insite confusion.

 

10 mile markers work fine, I have found personally that 6 minneys keeps things much more focussed and accurate.

 

David, im very curious how you find ground speed by watching the IAS in a 360, can you elaborate?

 

 

[deadstick]

Well I use 10 mile markers purely cause thats what I was taught, in the military we use 10 mile markers for high nav with the elapsed time for the leg in the rocket box, also we use 1 minute markers for low level Nav, the problem if I remember correctly is to do with having an accurate base and ground speed (210kts for the PC9)using the temp and wind for the day/time. Though our goal is to hit a target in +/- 12 seconds, The base speed allows us to adjust for wind i.e. if we hit the first waypoint behind time we have a reserve of power to catch up alternatively cut the corner on the next turn point, if your fast track left or right 60 deg for 1 minute then reverse 60 deg for one minute and you lose 1 minute track time. I cant see a problem using 6 min markers after all normal NAV is all about situational awareness rather than timing so whatever works for you. In my Jab I plan for 110kts (1.8nm/ min) fast cruise and 100kts (1.6 nm /min) for 75% cruise and then adjust for the winds on the day noting I havent encountered any wind thats been strong enough to stop me reaching my base speeds yet, (motor is strong after rebuild). Hope the Jabiru demon's didn't hear that! LOL:laugh:

 

 

[DarkSarcasm]

For what it's worth, I use 10 mile markers.

 

As long as the system keeps you on track and gets you to where you want to go, I'm not entirely sure what all the fuss is about. Use whichever you're comfortable with and works for you.

 

Iggy: I didn't realise you'd started navs. How are they going?

 

 

[Mazda]

Oh, I see, we are supposed to put WRONG things in here to see how people react.

 

 

[Guest burbles1]

I shouldn't think so Mazda. Only useful discussions should be posted. If cfi had been straight, there would still be useful replies from others stating their opinions - it doesn't take nonsensical spurring to evoke reactions.

 

 

[Guest davidh10]

...David, im very curious how you find ground speed by watching the IAS in a 360, can you elaborate?

Errr... No. It obviously won't work. Thanks for highlighting that. My mind was on several things while posting .

 

I've amended the original post. You can only use movement with respect to ground references and IAS to determine wind strength and direction manually without the GPS. Of course, heading versus track and IAS will give you some clues about cross-wind (more so in slower aircraft).

 

 

[motzartmerv]

;)...

 

 

[djpacro]

... it wasn't CFI that quoted the CASA and FAA manuals it was DJP....

I was thinking of also quoting the tutorials online here too but then I thought that everyone would be familiar with those Air navigation — completing the flight plan (xhtml w3c 01/10)

 

[motzartmerv]

Djp, did you give up on the CASA instructor manual?.

 

ENROUTE NAVIGATION

 

It must be stressed to the student that after the compass

 

the aeroplane’s clock (or a watch) is navigationally the

 

most important instrument, as the time factor is vital in

 

fixing a position. With a knowledge of the flight planned

 

time intervals between check points, regular reference to

 

a time piece will provide an approximate but continuous

 

indication of the aeroplane’s position, the value of which is

 

sometimes overlooked by the student (and instructors apparently) when too intent on

 

map reading. In essence the normal emphasis is on time,

 

then map followed by ground.

 

The normal emphasis is on TIME....then MAP......

 

 

[kaz3g]

Tomo said:

 

I just mark 10nm on the map along the track, makes it easier to calculate the leg distance as well...

 

The thing about the choice between miles and time is that miles remain constant. For those that are wondering, the time elapsed varies according to GS and I can't see the benefit in calling 6 minute marks 7 minutes or anything else.

 

If things go wrong are you going to have a quick look at your chart and call a position say 43 miles (4.3 divisions) SE of destination tracking...? Or are you going to tell the person who cares that you are 26 minutes SE of destination...?

 

When it happened to me the lady at ML CEN didn't know an Auster from a Navaho so she didn't really know what GS I had. But I was glad she knew where I was!

 

For what it's worth, I'll stick with the miles.

 

kaz

 

 

[djpacro]

Why would you think that, motzartmerv? I totally agree with the CASA Manual and your comments about watch-map-ground.

 

However, I thought that this thread was about what one scribbles on the map which was my reason for selecting the quotes - just those specifically relevant to the topic.

 

Here's an idea - perhaps allow posts with comments at the bottom of each page of the tutorials.