This is what I want to be able to do.
Plot a VFR flight plan on a map.
Have leg times calculated for me in minutes and seconds based on cruising speed.
Be able to edit each waypoint with what it is so I know what I’m looking out for.
I don’t think that’s a particularly demanding set of requirements, but blow me if I can’t find anything that even comes close.
MSFS built in flight planner. Cannot edit waypoints.
LittleNavMap. Cannot calculate leg times in seconds. (Also cannot import waypoint remarks into MSFS).
SimBrief. Doesn’t support VFR!
…anything else?
Anyone got any ideas please?
Moved to #community-support:aviate-navigate-communicate in Community Support since this is a “Need Help” topic.
Maybe this one - I don’t personally use it, but it’s none of the usual options.
Beyond that, maybe you’ll have to invest in the actual deal - like Garmin’s Pilot App.
Consider my (free) program GTFP. It does not calculate flying time, but it gives you the distance and you can just multiply that by your speed. The rest of your requirements it can do (in that you can name the waypoint after a visual clue). If you try it out and have concrete suggestions, I will consider implementing them.
VfrFlight doesn’t support MSFS, it also requires Java JRE and I don’t really want that on my system.
The Garmin stuff is way to pricey for me.
Thanks for the suggestions though.
Quick question - what is your intent of getting that granular with seconds between each leg?
For accurate navigation by dead reckoning. If you are navigating by dead recking you ideally want to have fairly short legs (to get regular reliable fixes and prevent errors accumulating over time).
Not having any seconds calculated for a 5 minute leg is a 20% margin of error. Travelling at 120kts a 60 second margin of error is over 2 miles.
Leg times calulated to the nearest minute are not remotely adequate for any kind of navigation by dead reckoning. You’d be calculating to the second even if you were piloting a boat or submarine let alone flying a plane!
Ok, I just wanted to see where you were going with this so we could talk on the same terms.
I don’t disagree with you, but most of the time if I’m getting that deep into a NavLog, I’m doing the math on my own. I have a nifty spreadsheet that takes some of the guesswork out, but also have the old E6B handy.
Interestingly, ForeFlight doesn’t even post seconds when waypoints are more than 10 minutes apart.
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DR is actually one of the topics on my upcoming stream this Friday.
I have just worked out that in LittleNavMap if you manually select the whole flight plan table and click copy it gives you it in csv format. So what I can do is load that into a spreadsheet, compute the leg times, and then just view that in MSFS using a kneeboard addon.
What’s your stream url please?
We started out with simple pilotage last week - just holding a course using visual checkpoints in light wind. I wasn’t going to delve much further into groundspeed checks (the plan was to introduce it this week along with DR), but I ended up doing a few examples along the way, which, expectedly, illustrated the problem of timing granularity. Interestingly, not so much with minutes and seconds, but with skyvector’s lack of decimal miles on the main map screen. That’s why I was interested in your comment.
In real life, do you REALLY split a flight into 5 minute legs??? On a 4 hour flight, that would be 48 legs! Wow, I NEVER did anything remotely like that in real life. To be sure, I used to fly many years ago in South Africa, so international best practices could certainly be different now than what I did there, then.
Note that I frequently flew multiple hour flights. I typically had 15 to 30 minute legs, depending on navaids, geographical features and standard/mandatory reporting points. Yes, for sure I ALWAYS kept continuous track of where I was by comparing points on the ground against my track on the map. In other words, if at any point in the flight you asked me to point out a landmark on the ground and the same on the map, I could always do that. Always. But never was I worried about to the second accuracy on any leg.
And FWIW: I was meticulous in my flight planning, including winds. If I was out more than 5 minutes on a 4 1/2 hour flight (typical time to get from Cape Town to Johannesburg in South Africa in either my C210 or Bonanza), I was rather annoyed with myself… That would be <2% error. And I did continuously compare actual drift angle to planned and actual vs planned leg times to verify actual wind direction & strength to forecast/planned winds. And at every reporting point I did update ATC with ETA’s at next reporting point and destination, as was the norm for VFR flights at that time.
And in MSFS I pretty much do the same.
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10-20nm between checkpoints/waypoints is often used for flight planning in the US, especially during training. This is 5-10 minutes at 120kts groundspeed. It is often a shorter distance for the first few checkpoints so you can establish the proper course and check groundspeed to make any adjustments before you get too far into the flight.
Realistically, in an area I know, with good visibility and not a ton of wind, it might be farther. Add a magenta line and it’s not so much crossing off checkpoints, but just correlating the map with what you see outside every so often.
I think how long your legs are will depend on the route. Here is an RAF instructor doing a low-level flight with dead reckoning.
He is using longer legs in this flight. but that’s because he’s flying mostly over open terrain. He’s still using leg times calculated to the second though.
If the flight were through a mountainous region following the valleys he would be using much shorter legs.
Leg length/time is going to be dependent on the factors I described above - speed, visibility (if you’re also using pilotage), and weather/terrain/obstruction considerations.
In the video, he’s doing over 400 knots, so a 5 second error is over 1/2nm, and a 20 second error is over 2nm. However, at that speed, his wind correction angle plays less of a factor than the leg timing.
In a 172 doing 120kts over the ground, it’s not necessary to be down to the second. Sure, you can strive for it, but the vagaries of the wind and effects of density altitude on performance, etc, are going to throw you off more than a few seconds timing error would.
When doing DR or pilotage in GA aircraft, I generally try to subdivide my timings into no less than a quarter of a minute (15s). Being off by an error of 7.5 seconds, either direction, will amount to a 1/4 mile deviation, which is well within the 3nm standards. And it’s easier to do the calculation to find 2.5, 2.25, etc on an E6B than converting directly discrete seconds into decimal minutes (which is how the E6B presents time).
But at that much lower groundspeed, converse to the high-speed example you provided, distance to turn is less of a factor than wind correction angle. Needless to say, both play a factor and taking visual or electronic nav cross-checks and recalculating from those is imperative and a good skill to hone. 
