Here are seven flight plans relative to the different US Air Mail lines, which were progressively set up at the same period of time, compared with the French Air Mail (Aéropostale).

I conceived this adaptation for Flight Simulator and X-Plane with two maps, the first dated 1924 for the East-West line, the second, dated 1927 describing the other lines starting along the East-West one.

Willian Boeing and Charles Lindberg worked for the US Air Mail.

Concerning (VII / Center East 2), composed of several short secondary routes, I did not respect them exactly, however, the cities mentionned on the map are present in the flight plan.

The 1927 map mentionned that certain parts of the lines were lighted, in order to make easier night flying at low altitudes. To my knowledge, those lightning systems did not exist on the French Air Mail lines.

34 pilots died on duty between 1918 and 1927 ; the Air Mail line towards Alaska started in 1938. 

The Curtiss "Jenny" proposed in Flight Simulator 2004, or equivalent, can be the historical right plane to be used, but the final choice remains yours. 
 
For further information and comments, you can join me  via the List of Members (michel95)

I / WEST - EAST

CALIFORNIA

San Francisco (San Francisco Intl KFSO) /27mn/ Concord (Buchanan KCCR) /48mn/ Sacramento (Sacramento Intl KSMF) 98mn

NEVADA

Reno (Reno/Tahoe Intl KRNO) /199mn/ Elko (Elko Regl KEKO) 173mn

UTAH

Salt Lake City (Salt Lake City Intl KSLC) 140mn

WYOMING    

Rock Springs (Rock Springs - Sweetwater KRKS) /84mn/ Rawlins (Rawlins Mun KRWL) /114mn/ Cheyenne KCYS 187mn

NEBRASKA

North Platte (North Platte Regl-Bird KLBF) /217mn/ Omaha (Eppley KOMA) 101mn

IOWA

Des Moines (Des Moines Intl KDSM) /95mn/ Iowa City (Iowa City Mun KIOW) 48mn

ILLINOIS

Moline (Quad-City Intl KMLI) /125mn/ Chicago (Chicago-Midway KMDW - Terrain utilisé à l'époque : Maywood) 147mn

OHIO

Bryan (Williams Co - 0G6) /120mn/ Cleveland (Cleveland-Hopkins Intl KCLE) 185mn

PENNSYLVANIA

Bellefonte N96 / 148mn

NEW JERSEY

New Brunswick - Manville (Central Jersey Regl 47N) 70mn

NEW YORK

New York - Islip (Long Island Mac Arthur KSIP - Terrain utilisé à l'époque : Hazethurat Field - Long Island)

II / WEST COAST

USA

WASHINGTON 1

Pasco (Tri-Cities KPSC) 203mn

IDAHO

Boise (Boise Air Terminal/Gowen KBOI) 252mn

UTAH

Salt Lake City (Salt Lake City Intl KSLC) 320mn

NEVADA

Las Vegas (Mac Carran Intl KLAS) 204mn

CALIFORNIA

Los Angeles (Los Angeles Intl KLAS) /95mn/ Bakers Field (Meadows KBFL) /87mn/ Fresno (Fresno Yosemite Intl KFAT) /137mn/ San Francisco (San Francisco Intl KSFO) /27mn/ Concord (Buchannan KCCR) /48mn/ Sacramento (Sacramento Intl KSMF) 229mn

OREGON

Medford (Rogue Valley Intl-Medford KMFR) /194mn/ Portland  (Portland Intl KPDX) 101mn

WASHINGTON 2

Tacoma (Tacoma Narrows KTIW) /19mn/ Seattle (Boeing Field/King Co Intl KBFI) 81mn

CANADA

BRITISH COLOMBIA

Victoria (Victoria Intl CYYJ)

III / EAST COAST

MASSACHUSSETS

Boston (Logan Intl KBOS) 81mn

CONNECTICUT

Hartford (Hartford-Mainard KHFD) 71mn

NEW YORK

Mineola - Bethpage (Grumman GRU) /18mn/ New York - Islip (Long Island Mac Arthur KISP - Terrain utilisé à l'époque : Hazethurat Field - Long Island) 70mn

NEW JERSEY

New Brunswick - Manville (Central Jersey Regl 47N) 49mn

PENNSYLVANIA

Philadelphie (Philadelphia Intl KPHL) 104mn

VIRGINIA

Washington (Ronald Reagan Washington Ntl KDCA) /89mn/ Richmond (Chesterfield Co KFCI) 140mn

NORTH CAROLINA

Greensboro (Piemond Triad Intl KGSO) /14mn/ Winston Salem (Smith Reynolds KINT) /18mn/ High Point (Darr Field NC03) 113mn

SOUTH CAROLINA

Spartanburg (Spartanburg Downtown Meml KSPA) 144mn

GEORGIA

Atlanta (The Hartsfield Atlanta Intl KATL) 117mn

ALABAMA

Birmingham (Birmingham Intl KBHM) /188mn/ Mobile (Mobile Regl KMOB) 113mn

LOUISIANA

La Nouvelle-Orléans (Armstrong New Orleans Intl KMSY) /44mn/ Pilottown - Port Sulphur -Birdwin 7LA1

IV / CENTER

ILLINOIS 

Moline (Quad City Intl KMLI) 224mn

MISSOURI

St Joseph (Rosecrans Meml KSTJ) /30mn/ Kansas City (Kansas City INTL KMCI) 161mn

KANSAS

Wichita (Wichita Mid-Continent KICT) 58mn

OKLAHOMA

Ponca City (Ponca City Mun KPNC) /76mn/ Oklahoma City ( Wiley Post KPAW) 162mn

TEXAS

Dallas (Dallas/Fort Worth Intl KDFW)

1st line : /78mn/ Waco (Waco Regl KACT) /140mn/ San antonio (San antonio Intl KSAT) /131mn/ Laredo (Laredo Intl KLRD)

2nd line : /195mn/ Houston (G. Bush Intercontinental-Houst KIAH) /49mn/ Galveston (Scholes Intl At Galveston KGLS) 

V / CENTER WEST

WYOMING

Cheyenne KCYS 78mn

COLORADO

Denver (Denver Intl KDEN) /62mn/ Colorado Springs (City of Colorado Springs KCOS) /33mn/ Pueblo (Pueblo Meml KPUB)

VI / CENTER EAST 1 

MINNESOTA 

Minneapolis (Minneapolis-St Paul Intl KMSP) /8mn/ St Paul (St Paul Downtown - Holman KSTP) 100mn

WISCONSIN

La Crosse (La Crosse Mun KLSE) /157mn/ Milwaukee (Gen Mitchell Intl KMKE) 70mn

ILLINOIS

Chicago (Chicago-Midway KMDW - Terrain utilisé à l'époque : Maywood) /111mn/ Peoria (Greater Peoria Regl KPIA /49mn/ Springfield (Capital KSPI) 84mn

MISSOURI

St Louis (Spirit of St Louis KSUS) 220mn

TENNESSEE

Memphis (Memphis Intl KMEM)

VII / CENTER EAST 2

NEW YORK

Albany (Albany Intl KALB) /9mn/ Shenectady (Shenectady Co KSCH) /97mn/ Syracuse (Syracuse Hancock Intl KSYR) /68mn/ Rochester (Greater Rochester Intl KROC) /48mn/ Buffalo (Buffalo Niagara Intl KBUF)191mn

MICHIGAN

Detroit (Detroit City KDET) 79mn

OHIO

Cleveland (Cleveland-Hopkins Intl KCLE) /54mn/ Youngstown (Youngstown-Warren Regl KYNG) 50mn

PENNSYLVANIA

Pittsburgh (Pittsburgh Intl KPIT) 65mn

OHIO

Akron (Akron Fulton Intl KAKR) /90mn/ Columbus (Port Columbus Intl KCMH) /66mn/ Dayton (Dayton-Wright Brothers KMGY /30mn/ Cincinnati (Cincinnati Mun-Laken KLUK) 83mn

KENTUCKY

Louisville (Louisville Intl-Standisford KSDF) 107mn

INDIANA

Indianapolis (Indianapolis Metro KUMP) 135mn

ILLINOIS

Chicago (Chicago-Midway KMDW - Original airport : Maywood) 

Copyright Michel Lagneau 2008

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