The Diversion

asechrest

asechrest

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asechrest
I am wondering how some of the CFIs here teach the diversion.

I've seen some unwieldy "diversion checklists" and I wonder if all that heads down time is appropriate. Hoping to pick up some "rule of thumb" tips that don't involve me heads down drawing lines all over the chart and fiddling with the E6B.

Thanks.
 
Turn in the general direction of where you are diverting before running through your calculations.
 
I just did my PPL checkride and talked about my diversion in my post-mortem thread I started today.

Basically, as Fox said - look at your map and determine the general heading you need to turn to - turn before you start working on anything else. If the diversion takes you from a west to east or vice versa heading, make sure you adjust for altitude.

When I did mine i didn't fiddle with my E6B (in fact, I didn't use my E6B at all on my checkride...intentionally). You certainly aren't going to do that in real life anyway. I use this method:

Look at your ASI or your GPS to get ground speed (I use ground speed off my 430) and divide that number by 10.

So, if your GS is 100 knots then your number is 10. That's how many miles you will travel over the ground in 6 minutes.

If your diversion is 20 miles then it's going to take you 12 minutes to get there. Add another 5 or so to get on the ground.

In my case, my diversion airport had a VOR/DME adjacent to it so I just tracked that over there. Good chance your diversion airport will have something similar that you can do. If not, you're going to likely have to do some pilotage to get over there as my DPE would not let me use my GPS D-> to track to the diversion airport. If there's not a VOR close to the airport find one that you can track a radial FROM to get there.

That's what I did in my checkride - talking outloud through my process - and my DPE after we arrived over the airport actually made a comment on how well I handled the diversion.
 
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...your CFI should have some intel on the DPE you are going to use. My school asks pilots completing checkrides to do a write-up that gets shared with other candidates. I read a few of those for my DPE and talked to a guy that had just passed about a month earlier and my ride was just about the same as his - same diversion. So, theoretically, you shouldn't have to go into a checkride having no clue what's going to happen. If you don't have that intel then you can count on diverting around your 2nd or 3rd checkpoint to somewhere 15-20 miles away. So, spend some time with your sectional to figure out possible spots you may go and what cues you'd use to get there.
 
for my diversion my DPE said "Look at that imaginary wall of clouds please go South" So I punched up an airport that I knew was South of my location. Unfortunately it was to the SE and deemed "unacceptable" and "try again" so I looked at the sectional and went a little over and punched it in to the GPS and was told "Land" as I was almost right over it by that point because I aimed the airplane Southbound at the first indication of "clouds" fortunately I landed at my diversion airport before a couple times so it wasn't new territory. It helps to know the area you are being tested.
 
kenjr said:
If you don't have that intel then you can count on diverting around your 2nd or 3rd checkpoint to somewhere 15-20 miles away.
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It varies.

My diversion was about 45 miles.

It's kinda scary, but I did it from memory...the DPE used a conversational approach to it, and I thought it was chatting....really! Good thing I was right.

Which way is Napa? That way [points out the left window], over Oakland.
How far is it? Just shy of 50 miles [most of us have rejected cross-countries there because it's ALMOST far enough].
How long? [Now it's obvious it isn't a chat] At 100 knots, 30 minutes.
Fuel? At low altitude through Oakland Class C full rich, 12 GPH = 6 gallons.

I'm still surprised that was good enough for the DPE. But Napa really is easy to find by pilotage, following the eastern bay shore or I-80 until it's in sight.

It turns out that if you pull out a sectional and draw a straight line from where I was (just south of VPKGO) to Napa, you'll go right over Oakland and it's 45 miles.
 
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My DPE said, and I quote: "I've changed my mind, we need to go to 'xxx.'"

Ok I said, making about a 150 degree turn, simultaneously climbing 1000 feet and then tells ATC that we were diverting [they already knew we were on a checkride]

His first question: Why did you turn? "You want to go XXX, right, its that way" - acceptable answer

How do you know? Well, thats the GW Bridge out in front of us to the east, where you want to go is west of there - so that can't be the right way. . . "

Next question, why'd you climb 1000 feet? "Higher is better, I've known that since college". . . . he actually smiled at that.

Why did you wait to call ATC? "We're VFR, I'm paying for gas and I'm not flying 10 feet further away from from where I am now going. . . "

I think I passed right there -
 
Obviously, there seems to be a number of ways to handle this. Most important to me was situational awareness. Know where you are, and where you need to go with your diversion. On my checkride, it was pretty simple. It was after the upset attitude testing and so I was about as discombobulated as I was going to be. He basically said that conditions were worsening, and limited my fuel, and added an inflight emergency to the conditions and okay what are you going to do. Basically, I checked around figure out where I was, pointed it out on the chart, and looked for the closest airport. Told him I was going here, as I turned the plane in that direction, and then told him I was going to call ATC to tell them what was happening. It was nontowered, and he question why not go to a towered airport. He asked what frequency I was going to use, and told him I was going to XXX.XX and the wanted to know why. I told him it was on the chart as the appropriate frequency. He had me go through what I was going to say. He asked if I could use any other frequency as well. By this time we had my diversion is sight, we did an engine out landing, and somehow the plane fixed itself after that. Miracles do occur!
 
2 lines of latitude (the horizontal lines) on the sectional are separated by 30 minutes which equals 30 nautical miles. If you are in a 152 doing 90 kts and using 6gph, this also equates to 20 minutes and 2 gallons of gas. If you place your pinky on one line of latitude on a line of longitude(the vertical line) and your index finger on the next, holding that spacing you can now measure distance, time, and fuel in one procedure to within the required accuracy of your diversion calculation with no plotter or E6B. Comparing the angle of your fingers against a line of latitude or longitude as you move them from your position to the diversion destination, you should be able to interpolate that angle/course within about 5° with a bit of practice and give a better correction to your initial rough turn towards your diversion airport.

Do NOT measure between two lines of longitude (holding your finger horizontally across the chart)as their spacing varies with latitude and only would indicate 30nm at the equator.

Check Ride Tip: Be prepared to be given a diversion to a location you do not have the fuel to make.
 
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From fold to fold on a sectional is approximately 35 nm. Top to centerfold is about 72 nm. Bottom to centerfold is 45 nm.
Now you have a really easy way to approximate distances without measuring anything.
Time is easy. Use 2 miles a minute and fudge factor up or down for your actual speed.
Then use these magic words. "We are approximately x miles and approximately x minutes and in direction Z from location Y. I'll refine that as I go."
 
You guys are great. This is exactly the kind of thing I was looking for thanks. Thanks everyone.
 
asechrest said:
Check Ride Tip: Be prepared to be given a diversion to a location you do not have the fuel to make.
Click to expand...

heh, I used my Cherokee 235 with 84 gallons of fuel on my checkride. That would have been an interesting diversion. :)
 
3 fingers on a sectional=about 10 nm. Measure your approximate distance from your present position to the diversion airport. If the diversion airport has a vor nearby, use the compass rose to grab a heading that will atleast get you pointed in the right direction. Use a little mental math to estimate your time and fuel enroute (20 nm in a skyhawk is typically going to be about a 10-15 minute flight. Adjust as needed based on the winds aloft). This is a quick and dirty way to get yourself on track-fine tune your numbers with the E6B/chart on the way (or in the real, post-checkride world with radio navigation aides if GPS is not an option.)
 
Checkride rescheduled from today to Tuesday. Thanks for the additional responses.
 
We had bad weather all week, so all of the DPE's scheduled rides got pushed back, including mine. This morning, which is when my ride was originally scheduled, it was literally the best flying morning we've had all summer. Cooler than normal, light breeze, not a cloud int he sky. Figures.

Now I'm rescheduled for Tuesday at 1:00pm. Whaddaya' want to bet we'll get the typical afternoon build-up and I'll get rescheduled again?
 
My (new) CFI has a pretty good system she taught me. Draw a line on the chart from where you are to the new destination. Seeing the line on the chart will instantly tell you if you're crossing restricted airpace, terrain elevation, VFR waypoints etc. Then I have the following little checklist pre-printed on my knee board that I fill in:

- Heading (extrapolated from a VOR on the chart)
- Altitude (based on terrain, airspace, VFR altitudes etc)
- Distance (measured by ruler/meridians etc.)
- Time (distance/2 assuming 120 kts cruise)
- Fuel (8pgh cruise = 0.8 gal for each 6 minutes)

Now you can take off towards the destination. While enroute, check:
- Compass (reset heading indicator)
- VOR/DME/GPS/other navaids to indicate your destination
- TPA, runways and L/R patterns
- Calculate begining of descent point.
 
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That's a nice method for planning a cross country, not a diversion. Have you tried to draw a 20 mile line on a TAC while flying afternoon thermals?

The real answer is to follow a road, river, transmission line, etc., perhaps a VOR radial, and only use the compass if those fail. Estimate distance with a finger and/or VOR roses (5 miles on a TAC, 10 on a sectional), or minutes of latitude.

Following ground features hugely reduces the effect of winds, and you can spot your new destination in terms of the ground features.

If you need to divert, it's often because someone is sick, they gotta pee, or you don't have enough fuel. None of those warrants fiddling with a chart for several minutes.
 
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asechrest said:
We had bad weather all week, so all of the DPE's scheduled rides got pushed back, including mine. This morning, which is when my ride was originally scheduled, it was literally the best flying morning we've had all summer. Cooler than normal, light breeze, not a cloud int he sky. Figures.

Now I'm rescheduled for Tuesday at 1:00pm. Whaddaya' want to bet we'll get the typical afternoon build-up and I'll get rescheduled again?
Click to expand...

Why? You should have adequate room underneath.
 
MAKG1 said:
That's a nice method for planning a cross country, not a diversion. Have you tried to draw a 20 mile line on a TAC while flying afternoon thermals?
Click to expand...

Yes, earlier today, as a matter of fact. To be clear, the above was designed as a method for executing a diversion ordered by a DPE who absolutely loves to send examinees through Bravo airspace. Real life would me more like a direct-to the nearest airport (at least for those of us who use the GPS).
 
Ateaist said:
Yes, earlier today, as a matter of fact. To be clear, the above was designed as a method for executing a diversion ordered by a DPE who absolutely loves to send examinees through Bravo airspace. Real life would me more like a direct-to the nearest airport (at least for those of us who use the GPS).
Click to expand...

That method of trying to work out a diversion will be a cluster **** to try to do in the plane likely leading you to bust altitude and heading if not attitude as well.best way to keep from busting airspace is by building a "fence" with VOR radial and through pilotage using highways and such.
 
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I always just rounded numbers (speed down distance and fuel burn up) to numbers I can wrap my simple mind around and estimate. For example I use 2nm/min to guess at time for my plane. I often am going faster but this is close enough (pre wind.)

Nothing is a substitute for knowing where you are at all times though, if you know where you are, where you want to go and can fudge something close on the wind correction angle you should be able to get there via simple pilotage.
 
Henning said:
That method of trying to work out a diversion will be a cluster **** to try to do in the plane likely leading you to bust altitude and heading if not attitude as well.best way to keep from busting airspace is by building a "fence" with VOR radial and through pilotage using highways and such.
Click to expand...

It actually works pretty well once you get used to it and can do it automatically. But I recognie it may not be the most efficient way.
 
This brings memories
I got diverted to 5K6 (Westosha) on my Private ride
Try finding that if you've never seen it before. Flew right over first time around, then played it smart and "bracketed" it with landmarks (roads, forest etc). I KNEW its right there... And then and only then I saw it. That was my opportunity to do the forwards slip too
Point being, "bracket" it. Some of those things are hard to find
 
Something a CFI can try is to give the student a diversion. After the student successfully diverts then immediately give the student a second diversion.
 
I was at 4.5k, planned was KASH to KABE which is 200nm. Diverted to KBOS about 10 nm west of KASH. Pointed the plane in the general direction of the field, tuned the VOR for the BOS VOR (asked my DPE to unfold the sectional since the BOS VOR freq was on the next page, got CRM points for this) and tuned the radio for Boston Approach to get the clearance.

As far as fuel goes, we're pointed east not west so ground speed increases, the max landing weight for a warrior is the same as its max gross for takeoff so there's no need to burn fuel for weight and BOS is visibly WAYYYYY closer to us the KABE.

So this means that we're (in order) aviating, and have enough fuel to do so until we reach the destination, we're navigating, and we're communicating which will come in handy for the bravo clearance.

The reason for the fuel check last is that unless you have waited until the last possible moment to divert, you have 30 minutes of fuel which in this area lets you get your diversion sorted out and then focus on the longer term (30+ min) problems

The only thing to have improved would have been a climb or descent of 1k, but we were headed into bravo airspace anyway
 
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GCA319 said:
3 fingers on a sectional=about 10 nm.
Click to expand...

You must have itty-bitty fingers. :rofl: 3 fingers for me (when I'm not drinking scotch) is about 15 nm.

Anyway, to get back on-topic, I just had a mock check-ride a few weeks ago and the instructor had me level off at 2,500' (instead of 4,500') which threw my TOC figure off and had me scrambling to calculate my next few checkpoints. Then, right as we were near the "flip-over" point of the sectional (about 15 miles out), he diverted me. So, I'm flipping the chart both ways AND trying to find a good checkpoint to get my GS from (he said the DME and the GPS were inop). This particular part of the chart has hash marks for an Alert Area, the info block for a (shutdown) VOR, a couple of airways, and a compass rose, so it was incredibly difficult to discern a checkpoint. Anyway, I took way too long to get my GS, but I immediately turned toward my diversion airport and just guess-timated my GS based on the winds at departure. I was pretty close on my ETA, but he said that the examiner they use wants to see that you do some basic calculations for the GS. Hopefully, when I do my checkride, the winds will be calm so I can just pretend I'm doing calculations :D.

This was my first mock and it was pretty intense. Before, it was always a lesson where we were working on, at max, 2 or 3 maneuvers; but now it was everything thrown at me in rapid succession. "OK, let's slow down and show me some slow flight." Did turns, climbs, descents, etc. Then, "since we're so slow, show me a power off stall." Then, "we're pretty low here, how about a turn about that tree." BAM, BAM, BAM....it just kept coming. It was exhausting. Now I know what to expect, so once I've got my "issues" corrected, I'll know what to expect on my next mock. Hopefully, that'll be the last one with an instructor. Then it's on to a mock with the Chief Pilot and then the examiner. :fcross:
 
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