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I did something to place a bit more challenge on myself than usual. After KS's suggestion in another post I decided to fly SMO to CRQ. All of this was hand flown, in a fast aircraft (Lancair Legacy),and +/1 100 ft altitude, and the kicker for me, (I'm a child of the magenta!), no GPS!

The TEC route is this: SMO SMO125 V64 V363 DANAH V23 OCN

The short story is that except for some bizarre wind shift caused by my weather engine I was able to keep the +/- 100 ft the entire trip at 250 ktas. Most everything went pretty well. But I have a few questions/things I could do better.

With a GPS, there is turn prediction, and I'm sort of used to this. With my ATC background I thought I had a good handle on when to turn but I'm usually a bit off. Is there a rule of thumb for certain airspeeds on when to turn to the next course? For instance, the turn from the SMO125R to intercept V64... it's not a sharp turn, but a decent angle of course change required. At 250 kts I think I turned about 16 miles from SMO (the leg is about 18 miles). I was too early on that turn, and had to fly more SE to get on V64. If the turn required was 90 degrees I typically use the same rule I use when vectoring aircraft to final approach course. 1/GS - so in my case 2.5 miles if I was doing 250 kts (ground speed assuming here). But I've found that's too early sometimes to actually join a new course. When I'm vectoring, the acft joins off a 20 or 30 (45 if helicopter) degree course intercept. But in a case where I need to make a 90 degree turn I'm trying to find a smooth turn to glide right onto the new course. How to do this?


Another thing... nearing OCN the controller told me "depart OCN heading 080." Does this mean I should treat OCN as a fly over fix? Or should I turn when I normally would (before the navaid), to a 080 heading? You might ask "how does a controller not know this!" Because we never use that technique where I work, and I don't know what the pilots would do.

Overall the flight when really well, I finished it off with a fast flown ILS Ry 24 at Palomar (I wussed out and should have done the LOC!)

I am no RW pilot but to answer your first question, take the same technique you use for PTAC onto a 90 degree intercept and apply it to this:
In this case, your turn from 125 to 74 degrees is 51 degrees (56% of the 90 degrees). So do something like 56% of what you would do for a 90 degree turn = Start of turn (1.4 from intersection) This is just a theory lol

As for the other question, per personal experience, this means they want you to overfly the OCN VOR and then fly heading 080.


Edit:
OR...... Playing around with some math (dangerous), I came up with these little references that seem to make more sense and in your case, you should have started a turn at 1.6 from intersection.

90 Degree turn:
GS/100 = Start turn

70 Degree turn:
GS/177 = Start turn

50 Degree turn:
GS/155 = Start turn

30 Degree turn:
GS/133 = Start turn

Ryan, fwiw, I posted that route for that pilot who was using a GPS on other flights and felt it was too easy. The main objective here was to post a route which is tricky to fly with GPS alone. If you approach this flight knowing you were gonig to be doing it sans GPS, it's just a series of radial intercepts, like any other VOR-based flight. So, if you found yourself wondering, "what's the big deal?" that's why. It's really only a challenge if you come into it thinking the GPS is going to fix all the issues

Peter has some great guidance on turn prediction, however, something is amiss with the model you're using. There is no way a Legacy will cruise at 250ktas under normal conditions.

It's a turbocharged version - I think I was just near the yellow arc - I can't recall my kias hehe

Keith Smith wrote:Peter has some great guidance on turn prediction,

No cred for Kyle

Hahahaha!

Peter has some great guidance on turn prediction

Why yes yes I do. See this post for it:

viewtopic.php?f=3&t=1316&p=8365&hilit=turn+lead#p8365

Thanks Kyle and Mr Grey

Well I might as well through my 2 cents into the mix.
I think the following is a good, reliable technique, but it does take practice. It requires math, but it need not be NASA exact.
Once you get the gist and practice it a few times, it will become second nature. And, more often than not, you will either hit the radial or be very close.
This works best for high performance airplanes that cruise at 180 kias or greater.
It also assumes a 90° intercept, (that is, 90° of turn,) but lesser intercepts will be explained. And it assumes a standard rate turn not to exceed 30°.
It is simplified from the 60 to 1 rule, and AFM 51-37.

You have to memorize two calculations; one determines turn radius, and the other determines the number of radials per nautical mile.
1. Turn radius “T/R”
For this part of the calculation one’s ground speed in nautical miles per minute must be known.
Then,
n.m./min - 2 = T/R.
2. Radials per Nautical Mile “R/M”
Knowing one’s turn radius is only half the equation. Radials “radiate” and become wider the farther away from the VOR you are located. So that value also must be known.
If not, you may turn too early for an intercept if you happen to be forty DME from the VOR.
Thus,
60 ÷ Indicated DME = R/M
Combing the two makes it easier to remember. So memorize: “Miles per minute minus two times radials per nautical mile, 30, 60, 90.” (The “30,60,90” will be explained later.)
n.m./min - 2 x R/M = Lead Turn.

Groundspeed: If you’re a whiz at math then use exact values. On the other hand, If one’s groundspeed, (n.m./min,) is not a whole number then round up, or down to the next whole number.
(4.8 n.m. /min = 5, 3.3 n.m. /min = 3. Etc.)
If groundspeed is not known or associated with the DME readout, one can still determine groundspeed.
If flying directly "to" or "from" a station, determine groundspeed by noting the distance travelled in 36 seconds, multiplying that value by 100, and dividing the sum by 60.
(E.g. 2.2 n.m in 36 seconds. 2.2 x 100 = 220. 220 ÷ 60 = 3.6 n.m./min.)

Radials: Radials per nautical mile is found by dividing one’s indicated DME into 60.
Again, if you’re whiz, use the exact DME value. If not, then round up or down. However, for R/M, always round up or down to a number that divides equally into 60.
(22.8 DME = 20 / 13.0 DME = 12)
Notice that between determining T/R and R/M there is always some slop. Very rarely will the numbers pan out exactly.
Furthermore there are always variables that one cannot accurately standardize; variable winds, turbulence, pilot technique, etc.
For these reasons one must expect to adjust the turn rate as one begins the intercept. That is, one will monitor the rate at which the CDI is moving and compare it to the rate of turn.
The bank angle may have to be increased, or decreased to match the CDI.
As a personal technique, when I get within 30 degrees of the desired radial, I determine; am I going to overshoot, or undershoot the radial?
If I judge an overshoot, then I maintain my bank angle, (usually 30°,) allow the overshoot, and roll out on an intercept heading, (usually 25°.)
If I perceive an undershoot, then I can reduce the bank angle and allow the CDI to catch up, or stop the turn with enough of an intercept angle to complete the intercept as soon as possible.

What if my degrees of turn is less than 90°?
Always calculate the 90° intercept first! Then choose one of three intercept angles that most closely matches the degrees of turn.
The three intercept angles to choose from are 30°, 60°, and 90°.
In your example you are turning from the SMO R-125° to the SLI R-254°; 51°. Fifty-one degrees of turn is nearest to 60°, so use the 60 degree intercept value.
Determine the 90° intercept.
If the degrees of turn is closest to 60°, then use 2/3rd of the 90 degree value.
If the degrees of turn is closest to 30°, then use 1/3rd the 90 degree value.
To reduce confusion and for simplicity always choose one of the three intercept angles. And choose the one that is closest to the number of degrees that will be turned.

How it applies:
First determine your 90° intercept. In your example, you are established on the SMO R-125°, preparing to intercept the SLI R-254°, (a 51° turn.)
Your ground speed is 250 knots, (round down to 4n.m/min.) The intercept point is 8 DME, (round up to 10.)
“Miles per minute minus two times radials per nautical mile, 30, 60, 90.”
4 n.m./min -2 = 2. (Turn Radius in nautical miles.)
Multiplied by
60 ÷ 10 = 6 (Radials per nautical mile.)
2 x 6 = 12.
“30,60,90” (30°= 1/3rd, 60°= 2/3rd, 90°= 3/3rd)
The degrees of turn is 51, (nearest to 60°)
2/3rd of 12 = 8.
SLI R-254° (V8/64) + 8° = 262° (Lead Turn.)
When your airplane crosses the SLI R-262°, begin a standard rate turn to intercept V8.

Ryan B wrote: Another thing... nearing OCN the controller told me "depart OCN heading 080." Does this mean I should treat OCN as a fly over fix?
Or should I turn when I normally would (before the navaid), to a 080 heading?...

Overfly the VOR then turn.
If ATC said, “Depart Oceanside on the 0-8-0° radial,” then a lead turn to intercept would be appropriate.
If ATC wanted you to overfly the VOR, then intercept a radial, they would say, “Depart OCN heading 0-4-0, intercept the 0-8-0 degree radial.”

MAAAAATH!!

Thank you as well!