Mariano Monaldi was born 18 March 1917.

On 1 October 1938, he was commissioned (in Servizio Permanente Effettivo) and received the rank of Sottotenente.

In July 1942, Tenente Monaldi served in the 390^a Squadriglia of the 159^a Squadriglia. The unit was at the time still equipped with Fiat CR.42s.

On 10 July, the 9th Australian Division launched an attack in the northern sector of the El Alamein line. This was backed by all the Commonwealth Wings that targeted ground targets and the airfields of LG 20, LG 21 and LG 102, which resulted in heavy aerial fighting.
Between 11:05-12:40, twelve MC.202s from the 9^o Gruppo led by Maggiore Roberto Fassi escorted five CR.42s from the 50^o Stormo out to attack enemy troops in the El Alamein area and 30km south of El Daba. The fighters were two from the 73^a Squadriglia, four from the 96^a Squadriglia and six from the 97^a Squadriglia. In the target area, they spotted three stepped up enemy formations with eight P-40s at 2,000 meters altitude protected by 10 Hurricanes and 6 Spitfires at 5,000 meters.
Capitano Luigi Mariotti (96^a Squadriglia) attacked and claimed one P-40 while Tenente Alvaro Querci and Maresciallo Rodolfo Stoppani (both from the 73^a Squadriglia) claimed three shared damaged P-40s. The last duo couldn’t finish the attacks since they were attacked by more enemy fighters. The combat last for 20 minutes and the pilots from the 9^o Gruppo returned claiming six enemy aircraft; four P-40s and two Hurricanes. The claims were made by Luigi Mariotti, two P-40s by Capitano Fernando Malvezzi (97^a Squadriglia), one P-40 by Sergente Teresio Martinoli (73^a Squadriglia), one Hurricane by Sergente Bruno Biagini (96^a Squadriglia) and one Hurricane by Tenente Antonio Canfora (97^a Squadriglia). One Hurricane and one P-40 were claimed as probables by unknown pilots. Five MC.202s were damaged but not seriously.
The five CR 42s of 50^o Stormo had taken off from Abar Nimeir at 11.00 to attack Commonwealth troops between the coast road and El Alamein with 50T bombs. The 391^a Squadriglia was down to one operational CR.42 (MM5046) and two more were borrowed from the 389^a and 390^a Squadriglie for the sortie, which was flown by Sottotenete Armando Marini (MM5046), Sottotenente Francesco Jadanza and Sergente Pasquale Rivolta (MM8847) and the target was motor vehicles east of El Alamein.
After the bomb release the Italian pilots reported being attacked by twenty enemy fighters over the railway station of Alamein and Sergente Rivolta was shot down and killed. In the combat Jadanza claimed one P-40, one probable and one shared damaged with Marini, who also claimed a probable. Another probable was claimed by Tenente Monaldi (390^a Squadriglia). The four surviving fighter-bombers landed at 12:20.
At 11:55 eleven Hurricane IIcs from 73 Squadron had taken off for a free sweep over the front. The British fighters met five CR.42s at very low height (100 m) and Flight Sergeant Ernest Joyce (BP167/QO-L) and Flight Sergeant H. W. E. Packham (BN415) claimed one CR 42 each while Flying Officer John Pain (BN566) claimed to have damaged one more. It seems that, at 12:10, 73 Squadron in fact lost Hurricane BN557 piloted by the ace Flight Lieutenant John Selby, who was obliged to force land (CAT II), after having been hit by the CR.42s (it was reported that he had been shot down by some Bf 109s but there are no German claims of this).
It seems that the MC.202s from the 9^o Gruppo had met six Kittyhawk Ias of 250 Squadron that had taken off at 12:20 to bomb an area north of the Gazala railway station. They reported being attacked two times by Macchi fighters at 12:20 and losing Sergeant Walter John Mortimer (AK962/E) and Sergeant John Alastair Seabrook (AK657/V), both KIA.

Monaldi was promoted to Capitano on 18 March 1943. At the time he was servicing in the 50^o Stormo.

Monaldi ended the war with 1 probable biplane victory.

Claims:

Kill no.	Date	Time	Number	Type	Result	Plane type	Serial no.	Locality	Unit
	1942
	10/07/42	11:00-12:20	1	P-40 (a)	Probably destroyed	Fiat CR.42		El Alamein area	390a Squadriglia

Biplane victories: 1 probably destroyed.
TOTAL: 1 probably destroyed.
(a) Probably claimed in combat with Hurricane IIcs from 73 Squadron, which claimed 2 CR.42s and 1 damaged while losing 1 Hurricane (pilot safe). The 159^o Gruppo claimed 1 P-40, 2 probables and 1 damaged while losing 1 CR.42 (pilot KIA).

Sources:
A History of the Mediterranean Air War 1940-1945: Volume Two – Christopher Shores and Giovanni Massimello with Russell Guest, Frank Olynyk & Winfried Bock, 2012 Grub Street, London, ISBN-13: 9781909166127
Ali d’Africa - Michele Palermo and Ludovico Slongo, 2009 IBN Editore, ISBN 88-7565-060-8
Annuario Ufficiale Delle Forze Armate Del Regno D’Italia Anno 1943. Part III Regia Aeronautica – 1943 Istituto Poligrafico Dello Stato, Roma