A new 2./15 IAP was formed in January 1940 from 33 IAP (66 AB in Mogilev, VVS BOVO). This unit was equipped with Polikarpov I-153s.

After re-equipment, 2nd and 4th escadrilyas were based at Klooga (with 33 I-153 fighters, of which 12 with additional fuel tanks).

15 IAP performed combat missions from 28 February.

On 11 March, starshiy leytenant Senkevich (CO 2./15 IAP) claimed a “Spitfire” 20km south of Lahti, when escorting three bomber escadrilles (27 SB-bombers; also DB-3 of 7 DBAP are mentioned), which attacked a railway bridge between Riihimäki and Lahti. After bombs were dropped from 2,000m at 12:55 (Moscow time), three “Spitfires” were observed. Senkevich attacked the left-most Spitfire, opening fire from 200m distance and stopping his fire at 80m. He followed his prey down to 300m, after which ”the aircraft crashed into the ground, but did not explode”.
His wingman, starshiy leytenant S. V. Vasin attacked another “Spitfire”, which evaded the attack.
Flight leader Dmitriyev observed two “Spitfire”, and ordered his flight to drop the under-wing fuel tanks and attacked from 400m distance. He saw also a “Spitfire” falling helplessly to the ground, after which he chased the third “Spitfire” away from Vasin’s tail.
A flight of three Finnish Morane MS.406 fighters of Osasto Siren (LLv 28) took off from Pyhänniemi, Hollola, to intercept attacking bombers but returned without claiming anything nor losing anything.

Senkevich ended the war with 1 biplane victory.

Claims:

Kill no.	Date	Time	Number	Type	Result	Plane type	Serial no.	Locality	Unit
	1940
1	11/03/40	12:55	1	’Spitfire’ (a)	Destroyed	I-153		20km S Lahti	2./15 IAP

Biplane victories: 1 destroyed.
TOTAL: 1 destroyed.
(a) Possibly claimed in combat with Morane MS.406 fighters of Osasto Siren (LLv 28), which didn’t suffer any losses.

Sources:
Red Stars 7 - Talvisota Ilmassa - The Winter War In the Air - Carl-Fredrik Geust, 2011 Apali Oy, Tampere, ISBN 978-952-5877-04-5
Soviet Fighter Pilots 1936-1953 - Mikhail Bykov
Suomen Ilmavoimat part II – 1928-40 – Kalevi Keskinen and Kari Stenman, 2006, ISBN 952-99743-0-2