Problem planning classic flights

[BendyFlyer]

StearmanDriver, thanks for posting this, I am glad the sextant gauge has been made to work in FSX. This will be going into most of my fleet (most are pre GPS and that includes some jets) and looks like a lot of fun. It looks like I will have to fire the GPS Navigator and do it myself.

[Stearmandriver]

Sure thing. If you want a really exhaustive primer in dead reckoning and celestial nav, plus an awesome slice of history, go here and download the pdf of the book called "Air Navigation" (first item on page):
http://aafcollection.info/items/list.php?item=000198

It's the actual manual used to train Army Air Force navigators in WWII. If you like this stuff, it's fascinating. If you don't it's unbelievably boring . Naw, it's actually a really accessible presentation of the material. It IS exhaustive, but remember, these guys weren't doing it for simulation... but even a skim of the chapters on basic dead reckoning and celestial nav will give a good foundation. You'll be blown away by how precisely you CAN navigate without any radios or GPS, and how well it works in the sim. If you don't want to buy an E6B (or whatever the earlier version of it is called in the AAF manual), there's some good websites that do all the calculations for you. Maybe it lacks the "cool" factor of spinning the wheel yourself, but it's quick and free and yields the same information, and it's still up to you to understand and apply it!

https://www.e6bx.com/e6b/
http://www.luizmonteiro.com/Index.aspx

[BendyFlyer]

I picked up another issue that some find perplexing or confusing about flight planning in this era of aircraft or flight planning in general so this is probably the best place to discuss the issue.

How High or What Altitude to Fly

1. Terrain - what is the Lowest Safe Altitude on the Route? That is what is the highest mountain or hill or object on that route, you then need to add a minimum of 1000 ft to that object or terrain to stay above it. So if the highest terrain is 2000 ft then you can safely plan at a minimum of 3000 ft. Now if the aircraft cannot get above the highest terrain, for example areas in Europe, the Himalyas, the Rockies, the Andes you need to work out or go by a route that you can get the aircraft to climb to.

2. Performance - The Connie had supercharged engines or blowers this enabled you to overcome what is called critical altitude that point where the air going into the engine is no longer sufficiently dense to provide good power. The engine performance charts will give you this information along with the MP. Mixture and RPM settings and in this era of aircraft it was worked out as a sum figure of BHP setting, which was also in the engine tables. Take into consideration also as the altitude increases your TAS increases due to changing air density even though the IAS may stay about the same as a rule of thumb you can add about 2 knots to the IAS for every thousand feet above about 6000 ft to guesstimate you true airspeed. In real life you used the computer to get the difference between your pressure altitude, the outside air temperature and the IAS to come up with an accurate TAS. Also take into account the heavy you are the more fuel you will burn to maintain a given airspeed but as the flight progresses your weight will be reducing and your speed increases, so you can either say great and keep the same power settings or reduce the power and keep the same speed and have more fuel.

3. Pressurised or Unpressurised Cabin. On any aircraft to maintain flight and stay alive above 10,000 ft you need oxygen to breath, so you either wore a oxygen mask or you pressurised the cabin, The Connie is pressurised so you did not need to wear an oxygen mask, but on all piston engines that limit was generally reached at about F240 but here is the but, you probably could go higher but the regulations for aircraft required the fitment of drop down emergency oxygen supplies for passengers and this technology did not arrive until pure jets made their appearance. So your basically limited to F240 by engines and oxygen.

3. Winds - Wind speed and direction can change in any areas from ground level up to flight levels. No matter how high you can go there is no point at going as high as you can or planning to fly at an altitude where you have a very high headwind component and at high altitudes where the jet streams occur these can be very high indeed up to 150 plus knots. All aviation meteorological services world wide issue what is called a GRID CHART where the winds at block levels up to F400 are indicated in generally 10,000 ft blocks, so by looking at a grid chart you can get an idea of where the wind is coming from and what speed it is forecast to be. You can burn a lot of unnecessary fuel climbing at high power to get to an altitude where the winds were not in your favour. In real life it was an is not unusual to be changing altitudes up and down to search for the best wind factor.

So in summary you looking for the altitude that keeps you out of the rock filled cloud, gives you the best BHP for the least fuel burn and therefore the best speed for the least fuel and finally the least amount of headwind. And that is the reason most pilots were required to and do sign on an hour and a half before departure time you have a lot of thinking and planning to do for the day! These days in the airlines have sophisticated planning departments and tools via computers and this is all basically calculated out in advance along with the load sheets before the crew arrive, in the days of the Connie the Captain and Co-pilot did all this work. The briefing office or planning department just gave them the info to work with, and there were no computers and no faxes and no photcopiers so this stuff all came off morse driven teletypewriters and was reconstituted into basic information sheets, hand typed!