Lavochkin´s first

[Maveric]

Hi all,

this is Lavochkin´s first fighter project IL. Designated from Istrebitel Lavochkina. A joint project with S.N.Lyushin and also called LL from both designers. A mock-up should be inspected at Jan 1936. Anybody had a good 3view or pics with technical data?

Servus Maveric

(Source: FliegerRevue 1986)

 

[Pelzig]

I don't know the specifics on this concept, but the wing mounted weapons are most certainly APK recoilless cannons that seemed to be pretty vogue in some Russian designs in the early and mid 1930s.

 

[Apophenia]

...the wing mounted weapons are most certainly APK recoilless cannons...

Also explaining the position of the horizontal tail.

Is the dashed outline of a canopy meant to show a further development? My impression was that the LL mockup had a flush canopy with periscope for forward view.

 

[borovik]

Is the dashed outline of a canopy meant to show a further development? My impression was that the LL mockup had a flush canopy with periscope for forward view.

Absolutely. The Periscope was, this confirmed fact.
But that appropriately for racing plane, for fighter nonsense.

(Guns DRP-76 by L.V.KURCHEVSKIY)

 

[Apophenia]

...for fighter nonsense.

Thanks for the canopy confirmation Borovik.

On armament, some sources use DRP and APK interchangably. I presume that the LL would have also had a more conventional machinegun armament as per the Grigorovich I-Z?

 

[Speedy]

Hi

(Guns DRP-76 by L.V.KURCHEVSKIY)

I think it's an error.

On armament, some sources use DRP and APK interchangably.

But it isn't entirely correct.
DRP means Dynamo-Reaktivnaya Pushka - "Dynamic-Reactive Gun" aka recoilless rifle. It's general name for this kind of weapon, designed by Kurchevskiy. DRP-76 was 76 mm single-shot, hand-loaded infantry gun, designed for installation on light vehicles in reconnaissance units.
APK means Aviacionnaya Pushka Kurchevskogo - Kurchevski's Aircraft Gun, recoilles rifle especially designed for aviation. Kurchevskiy build many APKs, caliber from 37 up to 152 mm. Almost all of them were externally powered guns, reloaded from 5-10-rounds-magazine by compressed air mechanism. Most popular model i think was 76 mm APK-4, feeded from 6+1 round tubular magazine over the barrel and shoot 30-40 rpm.

 

[borovik]

This is not a mistake, at least not much.
According to D.Romanov "Air weapon combat"
http://www.airforce.ru/history/romanov/chapter3/page3.htm
and many other sources equally used as factory title: "76-mm aircraft cannon dinamoreaktivnaya DRP-76" and serial "APK-4.
More correctly, as the Speedy because these guns (except the APK-1) had an automatic battery charger (picture 2)

 

[borovik]

Unfortunately with a high probability it can be argued that there was no exact information, specifications and images are not preserved.
There are descriptions of several books, quote from "The Osprey encyclopedia of Russian Aircraft" by B. Gunston which almost entirely repeats V. Shavrov’s "The history of aircraft structures in the USSR"

IL Designated from Istrebitel Lavochkina, (Lavochkin’s fighter); joint project with S.N.Lyushin (deputy) and also called LL from both designers. Appearance similar to IP series but with pilot low in fuselage seeing through periscope. Seat and hinged windscreen raised for landing or for better view in emergency. Mock-up inspected 12 Jan 36 by Gen. Ya. I. Alksnis.
Eventually abandoned.

............ In addition there is an original figure S. Lyushin’s for books M. Arlazorov’s.
I can propose their own vision, speculative drawing:
The first is the possible appearance of the description of M. Arlazorov's
second reconstruction, as described A. Ponomarev's.
Fighter B. Cheranovski's "BICh- 17" with guns Kurchevski's "APK-4"

Sources:
Arlazorov M.S. "Front is through KB"
Ponomarev A.D. "The Soviet aircraft designers"
Sobolev D.A. "-Century history of flying wing"
Shirokorad A.B. "Without otkatnye aerogun 30-ies."

 

[hesham]

Hi,

I heard that also for Kurchyevski, there is anther BICh-type
fighter with DRP guns (not related to BICh-17).

 

[Avimimus]

Does anyone have a good references for the APK-11 or the high caliber (100/102/152mm) versions? I'm curious about their performance (high explosive charge, muzzle velocity)...

There was also a ship mounted one, correct?

 

[borovik]

APK-11
In 1932 Kurchevsky drafted 37-mm automatic cannon APK-11 (sometimes called the APK-37). On the device, it is similar to APK-4.
Arsenal cannon had two cavities (cassette), which housed 12 shots.
Another shot was in the In 1932 Kurchevsky drafted 37-mm automatic cannon APK-11 (sometimes called the APK-37). On the device, it is similar to APK-4.
Arsenal cannon had two cavities (cassette), which housed 12 shots.
Another shot was in the barrel. (Total ammunition - 25 shots on the cannon).
The length of the cannon with a nozzle and the tray is 1978 mm, without them - 1250 mm. Weight gun with empty magazine 39.1 kg.
Shots unitary, sleeve shell made of flammable nitro tissue, wooden pallets, and then plastic. Projectile fragmentation with its percussion fuse. Shell weight - 475-500 g, the weight of explosives 31 g, the Charge - 140-145 g. powder MSK. Initial speed tests - muzzle velocity - 438-475 m/s
http://epizodsspace.no-ip.org/bibl/tm/1993/7/pushki.html
http://www.e-reading.link/chapter.php/144922/54/Shirokorad_-_Taiiny_russkoii_artillerii._Posledniii_dovod_careii_i_komissarov_(ill).html

 

[Avimimus]

Thank you Borovik! It is a great help.


I'm once more in your debt.

 

[Vasily41]

I have always wondered, how did the APK reload?