From 1942 to 1945, over 8,000 aircraft such as the Bell Bell P-63 Kingcobra  were ferried from the U.S. to the U.S.S.R.through Canada and the Alaska-Siberia Air Road.  
Lend-Lease
 In
 1941, the United States began supplying Great Britain matériel to help 
them in their war efforts against Germany. Since U.S. law prevented the 
Government from extending credit to Great Britain and only permitted 
cash sales of war matériel, the supplies were on "loan" (1941 
Lend Lease Act).
The
 Lend-Lease act allowed the U.S. to supply items needed for national 
defence to Great Britain and almost forty other countries including the 
U.S.S.R. whose defence was crucial to the United States. The program 
cost nearly $51 billion from 1941 to 1946 with most aid going to the 
British Empire ($31 billion) and the Soviet Union ($11 billion).
USA-USSR Lend-Lease Agreement 
In October, 1941, the U.S. and the U.S.S.R. entered into a Lend-Lease agreement  American Lend-lease deliveries to the Soviet Union included aircraft, trucks, tanks, motorcycles, locomotives and railway cars, anti-aircraft cannons and machine-guns, submachine guns, explosives, field radios, radar systems, as well as foodstuff, steel, 
        other metals, chemicals, and oil and gasoline. 
Lend-Lease Routes to the U.S.S.R.:
1. North Atlantic Arctic Convoys : to  Murmansk and Arkhangelsk in northern 
        Russia
2. Persian Corridor : through Iran into Soviet Azerbaijan
3. Pacific Route : to Vladivostok by Soviet ships
4. Alaska- Siberia  Air Route
This post deals with the delivery of aircraft across the 6,000 mile Alaska-Siberia air route. 
The Northwest Staging Route and Alaska-Siberia Air Road (ALSIB)
From
 1942 to 1945, the United States sent over 8,000 military aircraft to 
the U.S.S.R. through Alaska. 
The aircraft were ferried from factories in California, the U.S. Midwest
 and northeast  to Edmonton, then flown along the Northwest Staging Route
 to Fairbanks where Soviet pilots took possession of the planes and flew
 them over the 
Bering Strait to Krasnoyarsk [the Alaska-Siberian air road (ALSIB)] and then to the 
      battle fronts. 
Northwest Staging Route and Alaska-Siberian Air Road
a) The Northwest Staging Route : 1942 -1945
The
 
Northwest Staging Route consisted of airfields  built or upgraded about
 every 150 km (100 miles)  from Edmonton, to Fairbanks, Alaska. The airfields were connected by the the Alaska Highway.
Northwest Staging Route
 U.S. Alaskan Wing, Air Transport Command : RCAF Station Edmonton
The
 Edmonton station became the headquarters of the U.S. Alaskan 
Wing, Air Transport Command. Two routes from the United States met in 
Edmonton.  One route 
originated at Great Falls Army Air Base, Montana, where aircraft bound 
for Russia were ferried from their manufacturing plants in Southern 
California.  In late 1943, a second route originating at Minneapolis, 
Minnesota for aircraft manufactured in the Midwest and northeastern 
United States was inaugurated.
 U.S.
 Army Post Office (#462) located at the Edmonton base handled the mail 
for the American servicemen and personnel stationed at Air Transport 
Command. The covers below were mailed from Edmonton.
 U.S. Army Postal Service No. 462, Edmonton to Harrisburg, Pa., March 17, 1944
Although
 U.S. Army Post Office (A.P.O.) no. 462 was located at the RCAF Edmonton
 base, the actual locations of the APOs was not given in the return 
address. 
U.S. Army Post Office #462, Edmonton, March 17, 1944
Free surface mail to the United States
The
 second cover was from the Office of Field Director, The American Red 
Cross to New Haven, October 18, 1944. Free mail service had not been 
extended to the Red Cross.
U.S. Army Post Office #462 to New haven, Conn., October 18, 1944
3 cents surface letter rate to the United States
b) Alaska- Siberia Air Road
The aircraft flown by 
        American crews to Fairbanks, Alaska, were handed over to the Soviets  and ferried to Krasnoyarsk 
        in Siberia by specially selected Soviet pilots of  the Ferry Aviation Division.
 The Ferry Aviation Division consisted of five 
        ferry regiments (PAP), each of which was responsible for a certain part 
        of the route:
1 PAP - 
        Fairbanks-Uelkal (1.500 km),
        2 PAP - Uelkal-Seimchan (1.450 km),
        3 PAP - Seichan-Yakutsk (1.167 kin),
        4 PAP - Yakutsk-Kirensk (1.331 km),
        5 PAP - Kirensk-Krasnoyarsk (965 km).
 In Krasnoyarsk "ordinary" 
        pilots took over, flying the newly arrived aircraft westwards via Omsk, 
        Sverdlovsk and Kazan to Moscow for further distribution to frontline 
        units. ALSIB-ferry crews were returned to Fairbanks by the Yakutsk-based regiment.  
 
ALSIB
  
Aircraft Types Ferried 
Three main types of combat aircraft were ferried to the Soviet Union under Lend-Lease:
- Fighter aircraft - Bell P-39 Airacobas and Bell P-63 Kingcobras
- Bombers - Douglas A-20 Havocs and North American B-25 Mitchells
- Transport Aircraft - Douglas C-47 Skytrains
Russian crews in Nome gather under the wing of a U.S. bomber destined for the Russian-German battlefront.
2006 Lend-Lease Monument : Fairbanks, Alaska
 In August, 2006, U.S. Secretary of Defence Donald Rumsfeld and his 
Russian counterpart Minister of Defence Sergei Ivanov were among the 
many international political, military, and diplomatic officials who 
participated in the opening of the Lend-Lease Memorial in Fairbanks.