Ilja Finn took part in the Spanish Civil War where he served in the 1^a Escuadrilla of Grupo 26.

He arrived in Spain on 5 September 1937

In October, his unit was based at Sagunto and Sabadal airfields, operating over Barcelona and Valencia.

On 12 October 1937 he claimed a shared Ju52 or Ju86 over Huesca together with Anatoly Serov and Yevgenii Stepanov.
Nationalist records do not confirm this loss.

On 26 October, Finn left Spain.

Finn claimed one shared biplane victory during the Spanish Civil War.

Claims:

Kill no.	Date	Time	Number	Type	Result	Plane type	Serial no.	Locality	Unit
	1937
	12/10/37		1/3	Ju52 (a)	Shared destroyed	I-15		Huesca area	1a/Gr. 26

Biplane victories: 1 shared destroyed.
TOTAL: 1 shared destroyed.
(a) May alternatively have been a Junkers Ju86. Not confirmed with Nationalist records.

Sources:
Air Aces Home Page - Jan Safarik
Caballeros del aire de la Guerra Civil Espaņola (1936-1939)
Carlos Castejon - Soviet Volunteer in the Spanish Civil War - Igor Gordelianov and Mikhail Zhirokhov with editorial assistance by Richard Karbowski, 2002 Small Air Forces Observer no. 100 kindly provided by Mikhail Zhirokhov
Geroi Sowetskogo Soyuza, 1987-1988 Moscow kindly provided by Sergey Abrosov
Stalin's Falcons - Tomas Polak and Christhoper Shores, 1999 Grub Street, London, ISBN 1-902304-01-2
The Legion Condor - Karl Ries and Hans Ring, 1992 Schiffer Publishing, ISBN 0-88740-339-5