P
- PAC, Philippine Aircraft Company Inc – Philippines
- PacAero, PacAero Engineering Corporation – United States
- Pacific Aero, Pacific Aero-Products Co. – United States, (1916–1917) > Boeing
- Pacific Aerospace, Pacific Aerospace Corporation Ltd – New Zealand
- Pacific Airmotive, Pacific Airmotive Corporation – United States
- PADC, Philippine Aerospace Development Corporation – Philippines, (1973–present)
- PAI, Pacific Aeronautical Inc – Philippines
- PAC, Pakistan Aeronautical Complex – Pakistan
- Palladium Autocars, Palladium Autocars Ltd. – United Kingdom, (1911–1925)
- Panavia, Panavia Aircraft GmbH – Germany/United Kingdom/Italy
- Pander & Son, Nederlandse Fabriek van Vliegtuigen H. Pander & Zonen – Netherlands
- Panha, Panha – Iran, (Iran Helicopter Support and Renewal Company)
- Panzl, Greg Panzl – United States
- Papa 51, Papa 51 Ltd – United States
- Paraavis, Moscow, Russia
- Paradelta Parma, Parma, Italy
- Paradise Aircraft, Paradise Industria Aeronautica Ltda, Feira de Santana, Brazil
- Paramania LLC, London, UK
- Paramotor Inc., Oyster Bay, New York, United States
- Paramotor Napedy Paralotniowe, Warsaw, Poland
- Paramotor Performance, Bandhagen, Sweden
- Paramount, Paramount Aircraft Corporation – United States
- Paraplane International, Medford, New Jersey, United States
- Parapower, Pilchowo, Poland
- Parascender Technologies Inc., Kissimmee, Florida, United States
- Parasport.de, Schwanewede, Germany
- Paratech, Paratech AG, Appenzell, Switzerland
- Paratour, Saint-Chrysostome, Quebec, Canada
- Paratrek, Auburn, California, United States
- Parker, Cal Y. Parker – United States
- Parnall, George Parnall & Company Ltd – United Kingdom
- Parrish Aircraft Xperimental Inc, Plantation, Florida, United States
- Partenair, Partenair Design Inc – Canada
- Partenavia, Partenavia Costruzione Aeronautiche SpA – Italy
- Pasotti, Legnami Pasotti SpA – Italy
- PATS, Philippine Air Transport & Training Services Inc – Philippines
- Paulista, Companhia Aeronáutica Paulista – Brazil
- Pawnee Aviation, Pawnee Aviation, Inc., Longmont, Colorado, and later McCook, Nebraska, United States
- Paxman's, Paxman's Northern Lite Aerocraft Inc – Canada
- Payne, Vernon W. Payne – United States
- Pazmany, Ladislao Pazmany – United States
- Pazmany, Pazmany Aircraft Corporation – United States
- PCV, Pregiate Costruzioni Volanti – Italy
- Pegas 2000, Prague, Czech Republic
- Pegase Aero, Pegase Aero Enr – Canada
- Pelegrin Limited, Adazi, Latvia
- Pemberton-Billing Ltd, England (1913–1916) > Supermarine Aviation Works Ltd.
- Pena, Louis Pena – France
- Pennec-Lucas, Serge Pennec & Paul Lucas – France
- Percival, Percival Aircraft Ltd – United Kingdom
- Peregrine, Peregrine Flight International – United States
- Pereira, George Pereira – United States
- Performance Aircraft, Olathe, Kansas, United States
- Personal Flight, Chelan, Washington, United States
- Pfalz, Pfalz Flugzeug-werke GmbH – Germany
- Phillips, Peter J. C. Phillips – United Kingdom
- Phillips & Powis, Phillips & Powis Aircraft (Reading) Ltd – United Kingdom
- Phillips & Powis, Phillips & Powis Aircraft Ltd – United Kingdom
- Phoenix, Phoenix Aircraft Ltd – United Kingdom
- Phoenix-Aviacor, Phoenix OKB, Aviakor Mezhdunarodnaya Aviatsionnaya Korporatsiya OAO – Russia
- Phoenix Flugzeugwerke, Phoenix Flugzeugwerke – Austro-Hungarian Empire, (1917–?)
- Phoenix Gleitschirmantriebe, Würselen, Germany
- Phoenix Industries, Inc., Southampton, New Jersey, United States
- Phönix, Phönix – Austro-Hungarian Empire, (1914–1919)
- Piaggio, Industrie Aeronautiche e Meccaniche Rinaldo Piaggio SpA – Italy
- Piaggio, Piaggio & Companie SpA – Italy
- Piaggio, Piaggio Aero Industries SpA – Italy
- Piaggio-Douglas, see PIAGGIO and DOUGLAS – Italy/United States
- Piasecki, Piasecki Helicopter Corporation – United States
- Piel, Avions Claude Piel – France
- Piel, Claude Piel – France
- Piel, Etablissements Claude Piel – France
- Piel, Piel Aviation SA – France
- Pietenpol, Bernard H. Pietenpol – United States
- PIK, Polyteknikkojen Ilmailukerho – Finland
- Pilatus, Pilatus Flugzeugwerke AG – Switzerland
- Pilatus Britten-Norman, Pilatus Britten-Norman Ltd – United Kingdom, (PBN)
- Pilots Right Stuff, Brannenburg, Germany
- Piper, Piper Aircraft Corporation – United States
- Pipistrel d.o.o. – Slovenia
- Pitcairn, Pitcairn Aircraft, Inc. – United States
- Pitcairn-Cierva, Pitcairn-Cierva Autogiro Company – United States, (1929–?)
- Pitts, Curtis Pitts – United States
- Pitts, Pitts Aerobatics – United States
- Pitts, Pitts Aviation Enterprises – United States
- Plage & Laskiewicz, Zaklady Mechaniczne A. Plage i T. Laskiewicz – Poland, (1920–1935) (Mechanical Works A. Plage & T. Laskiewicz) > LWS
- Plan, Max Plan – France
- Plumb, Plumb – United States
- Pober, Paul H. Poberezny – United States
- Podesva, Peter Podesva – Czech Republic
- Podesva, Tomás Podesva – Czech Republic
- Polikarpov, Polikarpov OKB – Russia
- Politechnika Warszawska, Politechnika Warszawska – Poland
- Pop's Props, Cooksville, Illinois, United States
- Porterfield, Porterfield Aircraft Corporation – United States
- Portsmouth Aviation, Portsmouth Aviation Ltd, United Kingdom
- Potez, Etablissements Henry Potez SARL – France
- Potez, Société des Avions et Moteurs Henry Potez – France
- Potez Air-Fouga, Potez Air-Fouga – France
- Pottier, Avions Pottier – France
- Pottier, Jean Pottier – France
- Powell, John C. Powell – United States
- Practavia, Practavia Ltd – United Kingdom
- Prescott, Prescott Aeronautical Corporation – United States
- Private Explorer, Private Explorer Inc – United States
- Privateer Industries, Florida, United States
- Procaer, Progetti Costruzioni Aeronautiche SpA – Italy
- Pro-Design, Natters, Austria
- Professional Aviation, Professional Aviation Services (Pty) Ltd – South Africa
- Progressive Aerodyne, Progressive Aerodyne Inc – United States
- Promavia, Promavia SA – Belgium
- Protech, ProTech Aircraft Inc – United States
- Pro Sport Aviation, Wingate, North Carolina, United States
- Prowler, Prowler Aviation Inc – United States
- Pulsar, Pulsar Aircraft Corporation – El Salvador-United States
- Putzer, Alfons Pützer KG – Germany
- PWS, Podlaska Wytwórnia Lotnicza – Poland, (WSK-PZL) (Panstowe Zaklady Lotnicze)
- PZL-Mielec, Polskie Zaklady Lotnicze Sp z oo – Poland
- PZL-Mielec, Wytwórnia Sprzetu Komunikacyjnego-Panstwowe Zaklady Lotnicze Mielec – Poland, (Wytwornia Sprzetu Komunikacyjnego – Transport Equipment Manufacturing Centre)
- PZL-Mielec, Wytwórnia Sprzetu Komunikacyjnego-Panstwowe Zaklady Lotnicze Mielec SA – Poland
- PZL-Okecie, Centrum Naukowo-Produkcyjne Samolotow Lekkich-Panstwowe Zaklady Lotnicze Warszawa – Poland
- PZL-Okecie, EADS PZL Warszawa-Okecie SA – Poland
- PZL-Okecie, Panstwowe Zaklady Lotnicze Warszawa-Okecie – Poland
- PZL-Okecie, Panstwowe Zaklady Lotnicze Warszawa-Okecie SA – Poland
- PZL-Okecie, Wytwórnia Sprzetu Komunikacyjnego-Panstwowe Zaklady Lotnicze Okecie – Poland
- PZL-Okecie, Wytwórnia Sprzetu Komunikacyjnego-Panstwowe Zaklady Lotnicze Warszawa-Okecie – Poland
- PZL-Swidnik, Wytwórnia Sprzetu Komunikacyjnego Im. Zygmunta Pulawskiego-Panstwowe Zaklady Lotnicze Swidnik – Poland
- PZL-Swidnik, Wytwórnia Sprzetu Komunikacyjnego-Panstwowe Zaklady Lotnicze Swidnik – Poland
- PZL-Swidnik, Zygmunta Pulawskiego-Panstwowe Zaklady Lotnicze Swidnik SA – Poland