Ryabtsev was born in Makeyevka in the Donetsk region in 1915.

Prior joining the army, he worked as an electrician.

In 1934, he graduated from the military aviation school.

In June 1941, Ryabtsev served as a leitenant and section leader in the 123 IAP of the 10 SmAD. The unit was at this time based in the Kobrin-Pinsk area. The unit was partially re-equipped with Yak-1s but as late as 19 June, only 20 Yak-1s were assembled at Imenin airfield and the unit thus started the war still equipped with Polikarpov I-153s.

At 10:00 on 22 June 1941, eight Bf 109Es from IV/JG 51 attacked four I-153s from 123 IAP flown by kapitan N. P. Mozhaev, leitenant Georgiy Zhidov (his second take-off during the day), leitenant Ryabtsev and leitenant Nazarov over the Brest fortress.
Zhidov claimed two shared Bf 109 shot down, but shortly afterwards his own aircraft was severely hit before another I-153 came to his aid. Mozhaev claimed a Bf 109 while Ryabtsev claimed another in a “taran” ramming attack after having expended all his ammunition. Ryabtsev managed to successfully bail out of his stricken fighter.
No German fighters seem to have been lost in this combat but Oberleutnant Karl-Gottfried Nordmann claimed an I-153 (most possibly Ryabtsev) at 10:10.

He later became deputy eskadrilya CO.

He was killed on 31 July when a Bf 110 attacked his Yak-1 (N1919) at low altitude during take-off from Edrovo airfield in the Leningrad area.
Some sources claim that Bf 109s from JG 54 killed him.

He was posthumously awarded the Order of the Patriotic War, 1st Class on 6 May 1965.

At the time of his death, Ryabtsev was credited with 1 biplane victory.

Claims:

Kill no.	Date	Time	Number	Type	Result	Plane type	Serial no.	Locality	Unit
	1941
1	22/06/41	10:00	1	Bf 109 (a)	Destroyed	I-153		Brest area	123 IAP

Biplane victories: 1 destroyed.
TOTAL: 1 destroyed.
(a) Claimed in a “taran” ramming attack during combat with JG 51. 123 IAP claimed two and two shared Bf 109s in this combat but these losses have not been possible to verify with German sources.

Sources:
Aeroram
All aces of Stalin 1936-1953 – Mikhail Bykov, 2014
Barbarossa – The Air Battle: July-December 1941 – Christer Bergström, 2007, Chevron Publishing Limited, ISBN 978-1-85780-270-2
Black Cross/Red Star Volume I - Christer Bergström and Andrey Mikhailov, 2000 Pacifica Military History, ISBN 0-935553-48-7
Soviet Aces 1936-1953
Soviet Fighter Pilots 1936-1953 - Mikhail Bykov
Stalin's Falcons - Tomas Polak and Christhoper Shores, 1999 Grub Street, London, ISBN 1-902304-01-2
Sturmovik Technika
Additional information kindly provided by Yuri Shakhov.