LAX to Hawaii w/o using GPS - How?

[davefr]

Just for the challenge, I'd like to fly from LAX to Hawaii (or maybe even a smaller island like Fiji) without using GPS.

 

Is dead reckoning the only practical way to do it within FSX? It seems like any course error could cause a miss and I'm not sure island based VOR's have the range to give you any location info until your relatively close.

 

How do you do it?

[Mark Hurst]

Just for the challenge, I'd like to fly from LAX to Hawaii (or maybe even a smaller island like Fiji) without using GPS.

 

Is dead reckoning the only practical way to do it within FSX? It seems like any course error could cause a miss and I'm not sure island based VOR's have the range to give you any location info until your relatively close.

 

How do you do it?

 

I think in practice it would be impossible with dead (ded) reckoning because that's based on estimates that you continually correct by noting discrepancies between waypoints. A quick look at the map suggests there are no intermediate waypoints possible between LAX and Hawaii. It may be possible to use celestial navigation, which would rely on FSX modelling the stars and Earth's rotation accurately. It has stars and the moon, so maybe it will work.

[longbreak754]

Use the High Altitude Airways option when creating the flight plan. Using the default FSX planner it shows virtually the same route as the GPS Direct option but if you then look at the NavLog it will give all of the details (intersections, headings, distances) required to follow the route manually. As the lengths between the various points are relatively small the 'hit and miss' factor will also be smaller....

[f16jockey_2]

it will give all of the details (intersections, headings, distances) required to follow the route manually

 

Doesn't count. No way of checking you're on the right track.

"No use of GPS" also implies not checking the in-flight map IMO.

 

Wim

[loki]

What type of aircraft? Airliners use INS for long flights over water. Otherwise celestial would be the next best option. NDB beacons do have a long range, but not that long.

[longbreak754]

Doesn't count. No way of checking you're on the right track.

"No use of GPS" also implies not checking the in-flight map IMO.

 

Wim

 

Maybe I haven't made myself clear but what I am try to say is use the FSX default planner to create the route and then note down the info of the route - the nav log gives the OP the info required to plan the 'sim' flight as you would in real life if you were going to use ANY manual form of navigation - i.e. fly on heading XXX for XX miles or XX mins then change to heading XXX for XX miles/mins and so on.

 

One would also assume that the use of a real map would be made to plan/mark the flight and used during the flight for reference........

[Mark Hurst]

One would also assume that the use of a real map would be made to plan/mark the flight and used during the flight for reference........

 

Have you looked at a map of the route between LAX and Hawaii? Sure, you can plan a flight using imaginary waypoints, but as there is no way to cross-check against them it's no more use than planning the trip as a single leg.

[kk5qz]

I would fly a rhumbline course corrected for magnetic variation (238 magnetic if my calculations are correct), then all you have to do is correct for winds aloft.

[Mark Hurst]

then all you have to do is correct for winds aloft.

 

And you don't foresee any problems with that?

[StringBean]

I would fly a rhumbline course corrected for magnetic variation (238 magnetic if my calculations are correct), ...

 

Important to note that 238 magnetic at LAX is a different true heading than 238 mag at HNL.

 

LAX>HNL is too great of a distance to navigate solely on a whiskey compass.

 

peace,

the Bean

[mallcott]

Important to note that 238 magnetic at LAX is a different true heading than 238 mag at HNL.

 

LAX>HNL is too great of a distance to navigate solely on a whiskey compass.

 

peace,

the Bean

 

Rubbish. It was done for fifty years or more.

 

What you mean is you don't have the capability to navigate via NDB or dead reckoning only. Entirely different.

 

How do you do it in the real world? Simple: Dead reckoning aided by celestial navigation; calculated drift and long range radio navaids aided by stopwatch and compass.

 

I say `simple`, but it's still something that is quite an achievement for a solo pilot. But it's do-able.

 

 

 

In combination they were good enough for a competent navigator.

[davefr]

I've had a long swim back to LAX:(

 

I took off from LAX and set the AP for the course calculated by Skyvector. After 7+ hrs and approx. 2200 nm. (16X sim rate) I peeked at my GPS and was about 300 nm to the North of the islands and unable to pick up a VOR station. HNL VOR has a range of

 

In the real world is an INS system required as a backup to GPS for long overwater flights?

[Mark Hurst]

238 magnetic at LAX is a different true heading than 238 mag at HNL

 

Google 'rhumbline'.

[ianhr]

There's a drift sight utility that makes long overwater flights a piece of cake - if you can glimpse the surface.

[mikeandpatty]

Any great circle route (shortest distance between two points) has a departure angle and arrival angle, no matter how short the distance. Initially, these would be True headings based on the Earth's grid. Unless you were heading due East/West or North/South, departure and arrival angles will be different, and the greater the distance, the greater the difference in these angles.

 

 

 

Consequently, in theory,our heading would be constantly changing through the flight, but that is somewhat impractical, requiring a constant (albeit quite small) bank angle.

 

Therefore, dividing up this great circle path into maybe 1/2 hr increments based on estimated ground speed (and using the closest line of longitude crossing your intended path), departure and arrival angles at each of these "waypoint nodes" can be calculated. Use the FS flight planner or sky vector, both of which use an approximate 3-D Earth grid, and they correct for magnetic variation at any node, giving you an updated departure angle from that node - or in other words the departure course to the next node. Not that this departure course is identical to the arrival angle at the node in question, and they are magnetic if you use FSFP or SkyVector.

 

In reality, the slower your cruise airspeed, the greater your off course errors will be due to wind or other factors, but if your estimating is decent you will pick up a recognizable landmark or nav signal.

 

In the old days, a navigator and bubble sextant was a great help in refing estimated fixes based on star shots and sun lines.

 

Although I was a Naval Aviator, I learned this process as a Midshipman and Commissioned Officer serving aboard various ships. it stood the test of time from the 1800's until the advent of LORAN, essentially.

 

Hope this helps

[Mark Hurst]

There's a drift sight utility that makes long overwater flights a piece of cake - if you can glimpse the surface.

 

if your estimating is decent you will pick up a recognizable landmark

 

At the risk of labouring the point, there are no landmarks.

[longbreak754]

Have you looked at a map of the route between LAX and Hawaii? Sure, you can plan a flight using imaginary waypoints, but as there is no way to cross-check against them it's no more use than planning the trip as a single leg.

 

AND

 

At the risk of labouring the point, there are no landmarks.

 

I am well aware that there are nothing but water along the route. As indicated by others in the thread there are a number of ways to cross-check your position - not easy but as has already been pointed out, achievable.

 

WRT to maps - there are High Level airways charts available that show the routing/position of the Airways, Intersections, etc with KNOWN 'fixed' locations (based on Lat/Long) and distances between them. This info can form the basis of creating a route along the airway itself, and can be then used as a cross check reference point against your current position derived from whatever method has be used to get it thus allowing your calculate and adjust your course as required.

 

For example, when you 'arrive' at waypoint A you take a fix and plot the location on your map. You can then compare that location against the known location of waypoint A, make the necessary calculations and enter the new heading required towards waypoint B. As stated, not easy but achievable.

[Mark Hurst]

As indicated by others in the thread there are a number of ways to cross-check your position

 

Well no, there is one way (the one I pointed out).

[napamule2]

I can leave any West Coast area and hit Honolulu smack dab in the middle. No math. Just go 'World/Map' and zoom out. You can point your airplane (or boat) right at Hawaii and hit any Island you choose. In real time or speeded up (4X). Too easy. Use my head.

Chuck B

Napamule

[mikeandpatty]

I am talking about in the area of your arrival, not enroute - just like "Lindy"

[davefr]

I can leave any West Coast area and hit Honolulu smack dab in the middle. No math. Just go 'World/Map' and zoom out. You can point your airplane (or boat) right at Hawaii and hit any Island you choose. In real time or speeded up (4X). Too easy. Use my head.

Chuck B

Napamule

 

I wanted to try it with std. aircraft instruments. (no GPS and no World Map). World Map is a FSX tool vs. a std. aircraft instrument.

[ianhr]

The problem with drift calculation over water in the real world is that the surface is moving independently (and often unpredictably) and it's difficult to allow for this, particularly over the distances we're talking about here.

 

Odd that it worked so well for so long. I think you'll find that while the surface moves up and down a lot, any lateral motion is small enough to be ignored.

[Mark Hurst]

Only at high airspeeds. At lower airspeeds, particularly over long distances, drift errors can be significant. Even surface motion of just a few knots can make a big difference.

 

And in FSX that will depend on which REX texture you're using for the water! :pilot:

[PhantomTweak]

I wanted to try it with std. aircraft instruments. (no GPS and no World Map).

Actually, GPS IS standard these days. Even GA pilots carry hand-held GPS units they stick to the glareshield, just like you would in your car.

I know, this isn't what you want, just letting you know. GPS is a pretty "standard instrument" anymore. Not long ago, it wasn't, I understand. I remember when GPS first hit the market, I had to use it for my job. Had to have exact Lat/Long for some remote beacons, for correcting a radar's display to account for the movement of it's platform. The GPS we had was a large gym-bag full of electronics. It was as long as I am tall, and about 3' in diameter.

We had to go to location we were considering for the beacon, set up an antenna on a tall pole, and gather satellite data there for at least 2-3 hours, preferably more, then return to base, plug into a 286 computer and massage the data gathered for another couple hours to get the exact location.

Nowaday, GPS is a small, hand-held device. Incredible. You don't even need to check the satellite constellation info to make sure you'll have enough sats visible.

Thank you military for releasing GPS to the public!

 

Have fun, however you navigate.

Pat☺

[JSMR]

A lot of what ifs and maybe and coulds and how’s etc.

 

Just try it and see what happens? :). Much safer from the comfort of your home then in real life too. :)

 

I’d try it with zero wind and get the heading from FSX planner first. But don’t save it so you can cheat. Remove the GPS and the world ctr-s view or whatever it is in FSX. Hey, don’t want it too easy! :p

Then if you make it, download the wind and try and allow for drift. Not sure of the calcutions required. My maths not so good anymore.

 

It’s possible because Sir Charles Kingsford Smith and Charles Ulm flew from Oakland USA to Brisbane Australia in 1928. Some say a greater feat then man going to the moon due to the exact problems you are all facing just trying to get to Hawaii from LA. :)

 

That leg took ‘Smithy’ 27 hours and 25 mins. So depending what aircraft you use, expect to be sittIng there for some time. :D