Ikarus IO

File:Liberty L-12-1.jpg

After the crash of the Ikarus IM prototype reconnaissance seaplane (Serbian Cyrillic:Икарус ИМ – Извиђач Морнарички) with {{convert|260|hp|abbr=on}} BMW IV engine, on 31 May 1926, Ikarus immediately started development of a second reconnaissance seaplane prototype powered by a {{convert|4-00|hp|abbr=on}} Liberty L-12 engine, also designed by Josef Mikl, the Ikarus Technical Manager. The new prototype was named Ikarus IO (Coastal Reconnaissance) and the first test flight took place from the Danube at Novi Sad in September 1926.

After all-round tests, the aircraft was given a positive assessment and the Naval Air Force ordered the first series of 12 aircraft, which were delivered during 1927, serialled 101 to 112. Based on observations arising from the operational use of the aircraft, certain modifications were applied and another 24 modified IOs were ordered, receiving serials 113 to 136. In parallel with the development of the second IO series, Ikarus built prototype aircraft powered by a Loren engine.Петровић, Огњан М. (2/2000.). "Војни аероплани Краљевине СХС/Југославије (Део I: 1918 – 1930.)" (in (Serbian)). Лет – Flight (YU-Београд: Музеј југословенског ваздухопловства) 2: стр. 21–84. {{ISSN|1450-684X}}

The Ikarus IO was a flying boat with completely wooden structure, with wings rounded at the edges and covered with canvas. Auxiliary floats increased the stability of water-borne navigation. The two flight crew members, scout and pilot were seated side by side in parallel and the gunner sat in front of them in an open position with a Scarff ring gun mounting. Painted light gray, the aircraft were used in coastal reconnaissance and bombing roles and could carry about {{convert|250|kg|abbr=on}} of bombs and were armed with a {{convert|7.7|mm|in|abbr=on|3}} Darne machine gun mounted on the gunner's Scarff ring.

Markings subtypes of these aircraft were fitted with engines, according to [1]:

;IO/Li:

Coastal Reconnaissance seaplane with {{convert|400|hp|abbr=on}} Liberty L-12, (36 copies + 1 prototype built the 1927th and 1928 when available).

;IO/Lo

:Coastal Reconnaissance seaplane with {{convert|450|hp|abbr=on}} Lorraine-Dietrich 12Eb, (1 copy – a prototype conversion 1929th year)

;IO/Re

:Coastal Reconnaissance seaplane with {{convert|500|hp|abbr=on}} Renault 12Ke(1 copy – the prototype of the 1930th year 1937),

;IO/Lo

:Coastal Reconnaissance seaplane with {{convert|400|hp|abbr=on}} Lorraine Dietrich-12Db, (20 copies – Conversion 1934th year).

The IO was used by the Kingdom of SHS / Yugoslavia Navy as a coastal reconnaissance seaplane and light bomber from 1927 until 1941. The aircraft were deployed and served at Divulje, Vodice and Kumbor. Initially the IO suffered a high accident rate and by 1932 only 29 of the 37 production aircraft were still in service. Because of intensive use the Liberty engines were worn out and difficult to support necessitating substitution with Lorraine-Dietrich engines. In January 1941, 4 aircraft remained in service, of which two were airworthy, which were not used in operations before being withdrawn.

;{{flag|Kingdom of Yugoslavia}}

• Yugoslav Royal Navy

{{Aircraft specs

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|guns= 1x {{convert|7.7|mm|in|abbr=on|3}} Darne machine gun in the bow gunners position

|bombs= {{convert|250|kg|abbr=on}}

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{{aircontent

|see also=

• Ikarus ŠM

|related=

|similar aircraft=

|lists=

• List of aircraft of World War II

}}

{{reflist}}

1. {{cite book |last= Taylor |first= Michael J. H. |title=Jane's Encyclopedia of Aviation |year=1989 |publisher=Studio Editions |location=London |pages=528 }}
2. {{cite book

| last = Лучић

| first = Душан

| script-title=sr:Основи практичне аеродинамике са описима аероплана

| year = 1936

| publisher = Ваздухопловни Гласник

| location = YU-Нови Сад

| language = sr

| id =

| pages =

| chapter =

}}

1. {{cite book

| last = Микић

| first = Сава Ј.

| script-title=sr:Историја југословенског ваздухопловства

| year = 1933

| publisher = Штампарија Д. Грегорић

| location = YU-Београд

| language = sr

| id =

| pages =

| chapter =

}}

1. {{cite book

| last = Оштрић

| first = Шиме

|author2=М. Мицевски

| script-title=sr:Летећи Чунови: Чамци који лете – летјелице које плове

| date = 2007

| publisher = Галерија '73

| location = SRB-Београд

| language = sr

| id =

| pages =

| chapter =

}}

1. {{cite book

| last = Isaić

| first = Vladimir

|author2=Danijel Frka

| title = Pomorsko zrakoplovstvo na istočnoj obali Jadrana 1918–1941. (prvi dio)

| year = 2010

| publisher = Tko zna zna d.o.o.

| location = Zagreb

| language = hr

| isbn = 978-953-97564-6-6

| pages =

| chapter =

}}

1. {{cite journal

| last = Петровић

| first = Огњан М.

| date = 2000

| title = Војни аероплани Краљевине СХС/Југославије (Део I: 1918–1930.)

| journal = Лет – Flight

| volume = 2

| publisher = Музеј југословенског ваздухопловства

| location = YU-Београд

| language = sr

| issn = 1450-684X

| pages = стр. 21–84

}}

1. {{cite book

| last = Јанић

| first = Чедомир

|author2=Петровић, Огњан

| script-title=sr:Век авијације у Србији 1910–2010, 225 значајних летелица

| year = 2010

| publisher = Аерокомуникације

| location = Београд

| language = sr

| isbn = 978-86-913973-0-2

}}

• https://web.archive.org/web/20100113150445/http://www.paluba.info/smf/mornaricka-avijacija/ikarus-io-izvidac-obalni/
• http://www.pouke.org/forum/index.php?topic=5559.5;wap2 {{Webarchive|url=https://web.archive.org/web/20211203055027/https://pouke.org/forum/index.php?topic=5559.5;wap2 |date=2021-12-03 }}

{{Ikarus aircraft}}

Category:1920s Yugoslav military reconnaissance aircraft

Category:Flying boats

IO

Category:Biplanes

Category:Single-engined pusher aircraft

Category:Aircraft first flown in 1926