Piaggio P.108

Piaggio

Industry	Aerospace
Founder	Giovanni Casiraghi (designer)
Headquarters	Italy
Products	Aircraft, aircraft engines

Template:Infobox aircraft

File:Piaggio P.108 front quarter view.jpg

Piaggio P.108 front quarter view

The Piaggio P.108 Bombardiere represented Italy’s four-engine heavy bomber deployed by the Regia Aeronautica during World War II. Its inaugural flight took place on 24 November 1939, with operational service commencing in 1941. This aircraft was among the few Italian combat planes capable of rivaling the top Allied models.

Four distinct variants of the P.108 were conceived; however, only the P.108B bomber saw significant production prior to the armistice. The lineup also included the P.108A anti-ship model equipped with a 102 mm (4 in) gun, the extended-span P.108C airliner featuring a redesigned fuselage for up to 32 passengers, and the militarized P.108T transport version tailored for troop and cargo movement. Production numbers comprised one P.108A and twenty-four P.108Bs, while total units across all versions and prototypes reached at least thirty-nine, likely exceeding forty-four. Most of the P.108Cs were later converted into military transport aircraft capable of carrying as many as sixty passengers. The Luftwaffe operated nine P.108Ts within their transport squadrons until war’s end.

Design and development

The P.108 stands out in Italian aviation history as the only four-engine strategic bomber fielded by the Regia Aeronautica during World War II. It evolved from the earlier Piaggio P.50-II model, which suffered from insufficient power and a wooden frame that prevented it from achieving its intended maximum takeoff weight.

Giovanni Casiraghi, an accomplished engineer who had spent nearly a decade working in the United States from 1927 to 1936, was responsible for designing this innovative aircraft. Drawing on his international experience, he created a completely new all-metal low-wing bomber featuring retractable landing gear. Following a 1939 Air Ministry competition, the P.108 secured the Regia Aeronautica contract over rivals such as the CANT Z.1014, as competing designs were unable to promise timely delivery of sufficient aircraft numbers before the mid-1940s.

The initial prototype of the P.108B took flight on 24 November 1939. It demonstrated excellent performance throughout testing phases, requiring only minor adjustments; however, pilots needed time to familiarize themselves with its handling characteristics. The bomber was assigned exclusively to the 274a Squadriglia (274th Squadron) starting in 1941. Several accidents occurred during its service life, including one involving Benito Mussolini’s son, Bruno Mussolini, who commanded the squadron at that time. On August 7, 1941, while piloting one of the prototype bombers under secret development, he flew too close to terrain and collided with a house. The cockpit section detached upon impact; although no fire ensued, the aircraft was completely destroyed and Bruno Mussolini succumbed to his injuries.

By late 1941, accumulated flight hours for the P.108B amounted to just 391 hours; nonetheless, it exhibited considerable potential as a bomber platform. While average Italian bombers cost approximately two million one hundred thousand lire, with the Savoia-Marchetti SM.79 priced at around one million seven hundred thousand lire, the P.108's unit cost was substantially higher at five million two hundred thousand lire. This initially favored smaller bombers economically; however, when comparing payload delivery over equivalent distances, the P.108B demonstrated efficiency advantages: a squadron of nine P.108s could carry 3,500 kilograms (7,700 lb) up to 1,100 kilometres (680 mi), equating roughly to twenty-six SM.79s transporting 1,000 kilograms (2,200 lb) over 1,000 kilometres (620 mi) each. Total squadron costs were comparable—46.8 million lire for P.108s versus 45.6 million lire for SM.79s—but crew requirements differed significantly: fifty-four personnel for the P.108s compared to one hundred thirty for SM.79s.

The engines powering the P.108B were engineered to surpass those used in contemporaneous aircraft such as the B-17 Flying Fortress; furthermore, most defensive turrets featured remote control operation.

A subsequent iteration named the P.108B II emerged with modifications including removal of the nose turret. Although this reduced frontal defensive capabilities, it improved aerodynamics and decreased weight resulting in a speed increase of approximately ten km/h (six mph). Given that these bombers were primarily deployed in nocturnal missions, this trade-off was deemed acceptable.

Technical details

File:Piaggio P.108 nose.jpg

Similar to the Lancaster, the nose turret of the P.108 was mounted above the bombardier/bomb-aimer

The P.108 was a four-engine bomber constructed entirely from metal, accommodating a crew of eight. Its design, crafted by Giovanni Casiraghi, featured a highly durable and modern airframe capable of withstanding up to six g forces, predominantly fabricated from duralumin.

Crew accommodations included a dual-pilot cockpit and space for five to six additional personnel positioned around the midsection and nose of the fuselage. Unlike early B-17 Flying Fortress models, the P.108 did not incorporate a tail turret. A distinctive aspect was its nose design, which housed a dedicated compartment for the bombardier/bomb-aimer, topped by a forward turret—a configuration reminiscent of the Armstrong Whitworth Whitley with its lower section extending forward. The tail assembly was notably large to provide stability for the heavy and powerful aircraft, which weighed approximately 30,000 kg; 66,000 lb and delivered up to 4,500 kW; 6,000 hp during takeoff—about 20% heavier than early B-17 variants.

Engines and performance

Among Italian aviation manufacturers, Piaggio stood out for its ability to produce both airframes and engines. Their P.XII powerplants, though plagued by reliability issues, ranked among the most potent engines of their era. In contrast, Fiat, a significantly larger firm also engaged in aircraft and engine production, focused on models such as the conventional medium bomber BR.20 Cicogna.

The P.108 was powered by four air-cooled 18-cylinder P.XII radial engines, each delivering 1,010 kW (1,350 hp) at an altitude of 3,000 metres (9,800 feet) and 1,120 kW (1,500 hp) at takeoff. These engines drove three-blade constant-speed propellers designed by Piaggio. The P.XII itself consisted of two Piaggio P.X. engines linked in tandem; these were licensed adaptations of the French Gnome-Rhône 9K Mistral, which in turn originated from license-built Bristol Jupiter units. Similarly, Alfa Romeo lacked a modern high-power engine, with its AR.132s producing 1,010 kW (1,350 hp) by combining two Bristol Mercury engines in tandem.

The aircraft contained 12 self-sealing fuel tanks with a total capacity near 12,000 L (3,100 US gallons), complemented by eight oil reservoirs—two per engine—holding 350 L (90 US gallons) collectively. The heavy structure paired with powerful engines led to considerable fuel consumption. Consequently, the P.108 exhibited only average high-altitude performance, with an operational ceiling around 6,000 metres (20,000 feet) and a maximum theoretical limit near 8,000 metres (26,000 feet). For comparison, the B-17C could reach ceilings approximately 3,000 metres (9,800 feet) higher. This altitude capability aligned with other bombers of the period: the RAF's premier bomber—the Avro Lancaster—had a similar ceiling, whereas USAAF bombers like the B-17, B-24, and later B-29 were exceptional in reaching such heights due to their use of turbochargers and doctrinal emphasis on high-altitude precision bombing facilitated by devices like the Norden bombsight.

Maximum speed for the P.108 was about 420 km/h (260 mph) at an elevation of 4,300 metres (14,100 feet), which was slower than several biplane models. In contrast, the B-17C could achieve speeds near 515 km/h (320 mph) above 7,000 metres (23,000 feet), although its range and bomb capacity—3,220 km (2,000 mi) carrying 1,800 kg (4,000 lb)—were somewhat less than those of the P.108’s 3,335 km (2,072 mi) range with a 2,000 kg (4,400 lb) payload.

The aircraft could cover roughly 2,500 km (1,600 mi) while carrying bombs weighing up to 3,500 kg (7,700 lb), or extend its range to about 3,600 km (2,200 mi) when loaded with only 600 kg (1,300 lb) of ordnance. Although this performance surpassed typical Italian bombers—which generally managed only around with a payload near —it was less impressive compared to British and American counterparts such as the Avro Lancaster (capable of flying approximately carrying ) and the B-24 Liberator, which could cover about with similar bombloads. The SM.82, usually fueled with about half as much as the P.108 (approximately 5,500 L or 1,500 US gallons), could reach extended-range targets like Gibraltar when equipped with additional fuel tanks.

Bomb load

The P.108 featured an expansive bomb bay with the capacity to hold up to 3,500 kg (7,700 lb) of ordnance.

The payload configuration varied according to mission requirements, including:

• 7 bombs weighing either 250 or 500 kg (550 or 1,100 lb) each.
• 34 bombs of 100 kg; 220 lb (actual weight: 129 kg; 284 lb).
• 38 bombs weighing 50 kg; 110 lb (true weight: 69 kg; 152 lb).

Positioned centrally within the fuselage, the bomb bay was segmented lengthwise into three compartments, which restricted its ability to carry heavier munitions such as the 800 kg (1,800 lb) bombs. This limitation was significant when compared to the SM.82, which could handle larger payloads and operate effectively in both transport and bombing roles. When configured as a torpedo bomber, the aircraft could carry up to three torpedoes mounted beneath the fuselage and wings.

Defensive armament

The initial P.108 series was outfitted with eight Breda-SAFAT machine guns for defense. The nose housed a Breda "O" 12.7 mm (.5 in) machine gun loaded with 450 rounds, while a retractable ventral turret contained a Breda "G9" 12.7 mm (.5 in) gun supplied with 400-450 rounds. Alongside these hydraulically operated turrets, two 7.7 mm (.303 in) guns were installed on the sides, each carrying 500 rounds. The wings featured two hydraulically powered remote-controlled Breda "Z" turrets, each armed with 600 rounds and located in the outer-engine nacelles. These were operated from one of two cupolas positioned atop the fuselage "hump," each staffed by an operator. The wing-mounted turrets represented a pioneering element of the P.108's defensive technology.

Despite its advanced design, the practicality of the wing nacelle turret system raised concerns. While P.108s and B-17s both employed three main turrets for defense, the latter also incorporated dorsal, ventral, and tail gun positions. The P.108 had fewer guns overall (eight compared to ten to thirteen), lacked dorsal and tail turrets, and featured only a single machine gun in its ventral turret. The addition of wing turrets improved firing angles and visibility through dorsal cupolas but introduced complexity and certain operational drawbacks.

P.108A

File:P108 in volo 3.jpg

P108 in flight.

Developed following a November 1942 request, the P.108A Artigliere was designed as a heavily armed "gunship" for anti-shipping missions, intended to complement torpedo bomber units. It was equipped with an adapted high-velocity Cannone da 90/53 cannon installed in a redesigned nose section. Recognized as one of the most effective artillery pieces in service, this gun had multiple variants used by both Army and Navy for anti-aircraft and anti-tank purposes. For enhanced effectiveness in its new role, the caliber was increased from 90 mm (3.5 in) to 102 mm (4 in), an uncommon Italian artillery size, firing shells weighing 13 kg (29 lb) instead of the standard 10 kg (22 lb), with muzzle velocities exceeding 600 m/s (1,970 ft/s). The combined weight of the gun and recoil system was approximately 1,500 kg (3,300 lb). Given that it was essentially a re-bored smaller caliber weapon, its weight remained relatively low for its size.

This concept aligned with contemporary trends where medium bombers such as the North American B-25 Mitchell and smaller attack aircraft like the Henschel Hs 129 were being equipped with high-velocity 75 mm (3 in) guns.

The cannon was mounted along the fuselage centerline at a downward angle and generated substantial recoil forces that the airframe—weighting around 27 tonnes (30 tons)—could absorb. Ammunition capacity for this main gun ranged between 50 and 60 rounds; additionally, it could carry up to three conventional torpedoes or two radio-guided torpedoesTemplate:Fix/category, a classified weapon never deployed in combat. Defensive armament included wing and fuselage turrets. The 102 mm (4 in) gun was intended to be paired with a ballistic sight integrated with an analog computer and equipped with either a six- or twelve-round mechanical loader.

Initial alterations were applied to MM.24318, which flew to Savona on 16 December 1942 for modification work completed by February 1943; testing began on 3 March.

Performance trials yielded satisfactory results: aerodynamic refinements enabled maximum speeds near 440 km/h (270 mph). After flying to Furbara on 19 March and subsequently to Pisa on 16 April for firing tests conducted between altitudes of 1,500 and 4,500 m (4,900 and 14,800 ft), ballistic data necessary for developing the computing gunsight were gathered. Following approximately 24 hours and 40 minutes of flight and weapons testing, it returned to Albenga. Officially unveiled as the new attack aircraft at Furbara on 22 May, plans existed to produce five additional P.108As and convert between five or all existing P.108s accordingly; however, on 29 June production was capped at five units before being reduced further to two in July and ultimately cancelled altogether. On 6 and 8 September, the sole P.108A conducted further weapons evaluations over water equipped with the S. Giorgio calibration/aiming system.

Captured by German forces who repainted it with their insignia, the aircraft sustained damage during Allied bombing raids but was repaired by 7 April 1944 before flying to Rechlin where it likely met its end during subsequent air attacks.

Although demonstrating capability by firing over 280 rounds during testing phases, development ceased due to shifting priorities following the Armistice. Employing such large aircraft for perilous anti-ship roles remained debatable despite successful use of similar platforms like the B-17 Flying Fortress by US forces. At sea level, safe operational speeds hovered around 360 km/h (220 mph), while costs exceeded those of standard bombers; meanwhile, enhanced naval anti-aircraft defenses—including Bofors 40 mm Automatic Gun L/60, proximity-fuzed shells, and radar-directed fire control—prompted Germany's pursuit of guided munitions such as Henschel Hs 293 glide bombs and Fritz X.

P.108C/T

During the ongoing difficulties in developing the P.108B, Piaggio faced additional pressure due to a demand for new transport aircraft capable of long-distance routes to South America for Linee Aeree Transcontinentali Italiane (LATI). Although there were plans in 1939 to produce the Boeing 307 Stratoliner under license, this project did not materialize. Consequently, in 1940, the P.108C was proposed as a temporary transport solution while awaiting the arrival of the P.126C and the six-engine P.127C variants. These models were designed with a pressurized cabin to seat 32 passengers within a broader fuselage and were intended to be unarmed. The prototype took to the skies for the first time on 16 July 1942, by which point transatlantic routes were no longer operational. Despite this and Piaggio’s failure to deliver P.108B bombers promptly, an order for an additional five P.108Cs was placed.

The P.108T, a military cargo adaptation without pressurization, was ordered on 26 March 1941. This variant was equipped with a single Caproni dorsal turret, a ventral turret housing a Breda of 12.7 mm (.5 in) caliber, and two flank-mounted machine guns of the same caliber, reaching speeds up to 440 km/h (270 mph). Its ventral cargo door measured 4.8 m (15 ft 9 in) in length and 1.9 m (6 ft 3 in) in width, allowing it to accommodate two Macchi C.200 fighters internally. The aircraft’s internal volume exceeded 77 m³ (2,700 ft³), enabling it to transport up to 60 troops, eight torpedoes, or a payload of 12 tonnes (13 tons). After numerous design modifications, the first flight of the P.108T occurred on 7 September 1942. Although both P.108C and P.108T models were intended for use by the 148ma Squadriglia, production was limited before German forces assumed control over manufacturing; subsequently, at least eleven more units were completed.

A total of four P.108Cs and five P.108Ts were transferred to the Luftwaffe, serving primarily on the Eastern Front, especially during the evacuation of Axis forces after the Crimean Offensive in 1944. Compared with bomber variants, both the civil P.108C (configured as a 32-seat airliner) and military P.108T transport proved more dependable and valuable for carrying heavy loads such as two disassembled fighters—a significant asset given that the Luftwaffe had few heavy transport planes and mainly relied on smaller Ju 52 aircraft. These models featured defensive armament comprising four 13 mm (.51 in) MG 131 machine guns positioned in one dorsal turret, one ventral turret, and two waist gun stations.

One particular aircraft, nicknamed "Die General", was destroyed at Salonicco airfield. Most of these planes were operated by Transportfliegerstaffel 5 until war’s end; one was assigned to routes connecting Italy and Germany while others served on the Eastern Front. On 10 August 1944, an air raid resulted in the destruction of six units, with another four either destroyed or captured by 1945. A postwar iteration known as the P.108T-2 was proposed but never realized, marking the conclusion of the P.108 series’ development history.

P.133

By the time the Armistice was declared on 8 September 1943, the P.133 prototype—the final iteration of the P.108 series—was nearly finished. However, the project was soon abandoned, and the aircraft never reached completion.

The P.133 featured a lighter airframe and incorporated several performance enhancements, some of which were inspired by a captured B-24. It was projected to achieve speeds up to 490 km/h (300 mph), armed with six 20 mm cannons and four 12.7 mm (0.50 in) machine guns, while capable of carrying a bomb load as heavy as 4,800 kg (10,600 lb).

At the time of the Armistice, six units of the P.133 were under construction, with one approximately 90% complete. This nearly finished aircraft was concealed in a cave in Liguria but was eventually dismantled by Piaggio personnel.

In 1943, plans were underway to develop a civilian version for passenger transport, designated the P.133C, boasting a range of 5000 km. Nevertheless, no prototype for this commercial variant was ever produced.

Operational history

The P.108B models were active in both the Mediterranean and North African theatres. Their combat debut occurred during an unsuccessful daylight sortie against a destroyer on 6 June, deploying ten 160 kg (350 lb) bombs. A few weeks later, these aircraft conducted an effective night bombing raid over Gibraltar on 28 June 1942.

Gibraltar

The initial Gibraltar operation nearly ended in failure. Of five bombers that departed from Decimomannu in Sardinia, one (MM.22004) had to abort due to engine issues, while the remaining four dropped a combined total of sixty-six 100 kg (220 lb) bombs and six 250 kg (550 lb) bombs. Fuel shortages forced three aircraft to land in Spain; two (MM.22001 and MM.22005) either crashed or sustained damage during forced landings. The third (MM.22007) touched down in Majorca—a former Italian stronghold during the Spanish Civil War—and benefited from Spain's pro-Axis stance by quickly refueling and flying back to Italy from Palma de Mallorca. The other two aircraft remained in Spain: MM.22001 crashed near Valencia airport and was written off, while MM.22005 sustained minor damage and was stored at San Javier air base before being repaired and tested by the Spanish Air Force. Subsequent missions continued until October but resulted in additional losses and damage. Attempts were made to switch to SM.82s as a temporary solution, alongside reliance on the P.108 while anticipating improvements from the future P.133.

A timeline of sorties targeting Gibraltar (without repeating earlier endurance problems) includes missions on the night of 3 July (with MM.22601 failing to return), 24 September (involving MM.22004 and MM.22603), 20 October (featuring MM.22002—which was lost after an emergency landing caused by engine failure during takeoff—along with MM.22004, MM.22006, and MM.22007), and 21 October (including MM.22602—destroyed after an emergency landing at Bône in Algeria—plus two other P.108s). This period marked the operational peak with a total of fifteen sorties involving one to four aircraft each.

Despite modest tactical results—such as downing a Hudson bomber and damaging artillery positions—the strategic aim of compelling Allied forces to allocate significant resources defending this British outpost was achieved. This mirrored how just four S.82s had previously forced British defenses to protect oil refineries at Manama during the Bombing of Bahrain in 1940. On 28 October, MM22007 made a forced landing in Algeria during its third mission, culminating in at least sixteen sorties flown by this single aircraft with one lost, two interned in Spain, two destroyed in Algeria, and one lost within Italy overall.

Algeria and Africa

After the Allied forces launched the invasion of French North Africa, known as "Operation Torch", the aircraft involved encountered further losses during missions over Algeria and other African locations. The Allies deployed more than 160 warships alongside 250 merchant vessels in this theater. The Luftwaffe maintained a presence of 1,068 aircraft within the II and X. Fliegerkorps, while the Regia possessed 285 aircraft stationed in Sardinia, including 115 torpedo bombers. Throughout this series of attacks, at least three aircraft were downed over Africa, predominantly by Beaufighter fighters. Targets struck in Algeria included Bône (currently Annaba), Algiers, Blinda, Philippeville (now Skikda), Maison Blanche, and Oran.

During raids on Oran and other Algerian sites, some vessels sustained damage inflicted by P.108 bombers, which also succeeded in destroying several enemy aircraft. These bombers uniquely had the range to reach Oran, approximately 2,000 km (1,200 mi) away. The 274 Squadriglia operated only eight P.108s, conducting a total of 28 sorties over eight nocturnal missions within a month. Night fighters shot down three of these bombers; only once were defensive wing turrets able to fend off attackers. Two P.108s were downed by 153 Sqn Beaufighters during assaults on the Algerian port, with the final mission flown on 20 January. Mechanical reliability declined to just one or two serviceable aircraft, prompting their return to the mainland for refurbishment.

Sicily

The concluding engagements occurred over Sicily, where the 274ma was reinforced to a strength of eight aircraft. Between 11 and 22 July, they executed 12 sorties targeting the invading forces. Losses entailed two planes destroyed and two others severely damaged, primarily due to Beaufighter and Mosquito night fighter opposition. Only a single ship was hit during these operations, marking the end of both the 274ma's combat role and that of the P.108B.

The final delivery of the 24 ordered P.108Bs took place in August. Of these aircraft, six were lost due to enemy action—three over Algeria, two during Sicily operations, and possibly one over Spain—while four succumbed to accidents (including an incident involving Bruno Mussolini), and three were lost following forced landings (one in Algeria and two in Spain).

After the armistice

File:Pilots with Piaggio P.108 at Grottaglie 1943.jpg

At Grottaglie airfield in Italy, pilots Flight Lieutenant L. Wynne from Yorkshire, England; Squadron Leader Brian Eaton from Melbourne, Victoria; Flight Lieutenant Harris DFC from Adelaide, South Australia; engage with an Italian pilot who has just flown his four-engined Piaggio P.108 bomber from Northern Italy.

By the time the armistice was announced on 8 September 1943, only nine P.108 aircraft remained operational. Of these, eight were deliberately sabotaged to prevent capture by German forces; a single aircraft was flown south but suffered a landing accident upon arrival. The operational history of P.108Bs includes approximately 15 missions over Gibraltar, 28 over North Africa, 12 over Sicily, alongside various reconnaissance and anti-shipping sorties—only one of which is documented.

The complexity and challenging development requirements of this aircraft exceeded what could be supported without assistance from the Air Ministry or larger industrial entities like Fiat—support that never materialized. While Piaggio continued efforts to refine and produce the P.108B model, numerous other demands arose for variants such as the 'C' airliner version, the P.108T military transport, and 'A' anti-ship models. Additionally, plans existed for an advanced strategic bomber—the P.108bis or P.133—as a potential ultimate solution for Italian bomber needs, along with other projects like the P.126, P.127, and P.130 under consideration.

Following the cessation of combat missions by P.108Bs, several P.108T transport variants remained active until war's end—primarily on the Eastern Front—assisting German efforts to evacuate encircled troops while capable of carrying over 100 soldiers per flight (with a maximum payload near 12 tonnes/13 tons and total carrying capacity around 14 tonnes/15 tons). The P-108C and T models demonstrated greater reliability compared to their bomber counterparts after successful modifications and improvements were implemented. One transport was lost in a flying accident over Germany early in 1945; others continued service until hostilities concluded.

Variants

The exact production figures for the P108C and P108T remain uncertain; however, it is estimated that around 16 units were manufactured in total, with the majority of the P108C models later converted into the transport variant.

• Prototype: MM 22001
• Series 1: MM 22002–22008, MM 22601–22604
• Series 2: MM 24315–24326
• Series 3: MM 24667–24678

P.108 Prototype

P.108A Artigliere

Designed as an anti-ship aircraft, with only one unit produced.

P.108B Bombardiere

Heavy bomber variant, with a total of 24 built.

P.108C Civile

Civilian transport model, likely around six units constructed, though exact numbers are unclear.

P.108M Modificato

Proposed upgrade of the P.108B featuring enhanced armament; no examples were completed.

P.108T Trasporto

Transport configuration, exceeding twelve units including those converted from P.108Cs.

P.133

An advanced iteration of the P.108B incorporating improved engines and greater bomb capacity; project remained unfinished.

P.133C

Civil and military transport variant of the P.133 with a range of 5000 km, studied only during 1943.

Operators

Kingdom of Italy

Regia Aeronautica

Nazi Germany

Luftwaffe

Specifications (Piaggio P.108B)

File:Piaggio P.108.svg

Sources

• Angelucci, Enzo and Paolo Matricardi. World Aircraft: World War II, Volume I (Sampson Low Guides). Maidenhead, UK: Sampson Low, 1978.
• Bignozzi, Giorgio. "The Italian 'Fortress' (part 1)." Air International Vol. 31 No. 6, December 1986. pp. 298–305; (part 2) Air International, Vol. 32 No. 1, January 1987. pp. 29–31, 47–49.
• Garello, Giancarlo. Il Piaggio P.108 (Italian language). Rome: Edizioni Bizzarri, 1973.
• Giraud, Roger. "Les Piaggio de Bombardement, en petits raids hasardeux... (5)." Le Fana de l'Aviation, April 1976, issue 77, pp. 22–23 (in French).
• Knox, MacGregor. Hitler's Italian Allies. Cambridge University Press, 2000. ISBN 0-521-79047-6.
• Matricardi, Paolo. Aerei Militari: Bombardieri e da Trasporto 2 (Italian). Milano: Electa Mondadori, 2006.
• Mondey, David. The Hamlyn Concise Guide to Axis Aircraft of World War II. London: Bounty Books, 2006. ISBN 0-7537-1460-4.
• Pedriali, Ferdinando. "Le Fortezze Volanti Italiane." RID magazine, November 1991, pp. 60–65 (Italian).
• Sgarlato, Nico. "P.108, la Fortezza della Regia." Great Planes monographes, No. 27, March 2007. Parma, Italy: West-ward edizioni (Italian).

External links

• P108B.htm Piaggio P.108 SITE OFFLINE as of October 15, 2007
• Piaggio P.108 (Russian language)
• Comando Supremo P.108
• Regia Marina website featuring a P.108 article
• Special Hobby 1:72 Scale Plastic Model Review