Adaptation of the basic LaGG-3 airframe for a 14-
cylinder two-row radial Shvetsov M-82 engine without
major redesign of fundamental components resulted in
the La-5 (examples converted from existing LaGG-3 airframes on the production line sometimes being referred
to as LaG-5s). The prototype conversion was first
flown in March 1942 with an M-82 rated at 1700hp for
take-off, and the La-5 was cleared for service testing in
the following September with an armament of two
20mm cannon. With completion of the conversion of
existing LaGG-3 airframes, minor changes were introduced
in new production aircraft, the principal of these
being the cutting down of the aft fuselage decking and
the introduction of a 360°-vision canopy. Late in
1942, the improved M-82F engine became available,
producing 1650hp at 1650m, aircraft fitted
with this engine being designated La-5F, and, from
early 1943, fuel tankage was revised. From late March
1943, the fuel injection M-82FN engine offering 1850hp
for take-off replaced the carburettor-equipped M-82F,
and with this power plant the fighter became the
La-5FN. When the La-5 was withdrawn from production
late in 1944, a total of 9,920 aircraft of this type (including
La-5UTI two-seat trainers) had been built.
| Take-off weight||3360 kg||7408 lb|
| Empty weight||2800 kg||6173 lb|
| Wingspan||9.8 m||32 ft 2 in|
| Length||8.60 m||28 ft 3 in|
| Height||2.54 m||8 ft 4 in|
| Wing area||17.50 m2||188.37 sq ft|
| Max. speed||648 km/h||403 mph|
| Ceiling||11000 m||36100 ft|
| Range||765 km||475 miles|
|A three-view drawing of La-5FN (1660 x 1253)|
The twin VYa-23 WoF @ about 2.5 kps for the slowest but most dependable RoF, goes to 2.9 kps at the average RoF of 435rpm each. M/V is also world-beating.
The 20mm ShVaK and B-20 twin cannons are inferior on both counts. Their advantage is a denser pattern of fire for dogfights.
The weight of fire may be less than I posted before.
The B-20 was my basis for the ShVAK, which I thought was alike in RoF. However, The synchronized ShVAK may have been more like 610 rpm. 1.926 kg/s weight of fire for the twin cowl guns may be more accurate for the ShVAK. 615 rpm (1.974 kg/s) is also published but I picked the more conservative number. 20.33 rps to 20.5 rps vs 23.5 rps for twin B-20s.
June 1943 the initial La-5FNs entered battle. They were pieced together on the assembly lines alongside the La-5Fs
and their performance varied from aircraft to aircraft. Semi-typical performance of these machines was: Engine: M-82FN/1,850hp. WE. Speed: 351mph/SL. 384mph/19,000ft. Climb: 3,854fpm/SL. 16,400ft/4.8min. Ceiling: 35,000ft.
By September 1943 the La-5FN was being produced with all the refinements in place. The typical performance of this last production moder was: Same Engine. 359mph/SL. 396mph/19,500ft. Climb: 3,985fpm/SL. 16,400ft/4.6min. Ceiling: 36,080ft. All models of the La-5 retained the same armament: 2xShVAK (20mm). Test weight: 7,340 lbs.
The La-5F was further improved in the Type 39 model. It was lightened from the original La-5F and improvement made to the landing gear which eliminated the bouncing tendencies of all previous models. The Type 39 handling and maneuverability was greatly improved over its predecessors.
Aileron response now exceeded even that of the Yak-9. The Type 39 entered service in March 1943. Below I made a mistake: The original La-5F rolled off assembly lines in January 1943. The Type 39 La-5F had the following specifications: Test weight: 7,113 lbs. Engine: M-82F/1,700hp.WE. Max.Speed: 347mph/SL. 381mph/19,000ft. Climb: 3,745fpm/SL. 16,400ft/5.0min. Ceiling: 33,095ft.
The Type 39 was the first model of the La-5 that could outperform the LaGG-3 by a certain noticeable margin.
The La-5F entered service in March 1943 with the cut down rear deck and greatly improve engine cooling modifications.
Specifications: Engine: M-82F/1,700hp.WE. 344mph/SL. 373mph/20.5Kft. Climb: 3,690fpm/SL. 16,400ft/5.4min. Ceiling: 31,258ft. at 7,422 lbs.
The 'Standard' LaG-5 corrected most of the deficiencies of the early model. It entered service in August 1942. In September, the NKAP revised the production contract to codify the changes made and the fighter's nomenclature was revised to La-5. Engine remained the same as LaG-5. Loaded weight dropped from 7,407 to 7,385 lbs. Max.Speed increased to: 326mph/SL. 365mph/20.5Kft. Climb: 3,350fpm/SL 16,400ft/5.9min. ceiling stayed the same. 2xShVAKs (20mm).
It was still a disapointment to the VVS because it was outperformed by the LaGG-3-37 and a few other variants of the LaGG-3.
Found another performance listing of the early LaG-5 1942:
Engine and power the same. 332mph/SL. 363mph/20.5Kft. 3,350fpm/SL. 16,400ft/5,7min. 100fpm/31,000ft. at 7,385 lbs.
Performance of the initial batch of La-5 varied like all VVS aircraft but typical was: 316mph/SL. 360mph/20,500ft. Initial Climb: 3,225fpm. 16,400ft/6.0min. Service Ceiling: 31,000ft. at a weight of 7,407 lbs.
The initial production La-5 lacked leading edge wing slats and were powered by the Shvetsov M-82A radial delivering 1,510hp at take-off and emergency. Pilots noted that the performance was considerably less than they were led to believe. These machines were based on LaGG-3 airframes that had been rejected from production because they suffered from insufficient internal balance units for the control surfaces. Combined with the powerful torque of the M-82A resulted in poor control an considerable physical workload for the pilot. Cooling difficulties of the engine kept 50% of the machines on hand unavailable for operations until the arrival of the 'Standard' LaG-5 in August of 1942.
Thank you for those details. That is the reason I keep reviewing sights like this. Do you have a source we can reference?
This certainly helps explain the parity of Yaks with Lavochkins and the Luftwaffe mid-war.
The Yaks and LaGGs with M-105 engine all could take negative Gs from the M-105PA (1941) onwards as they were all equipped with floatless carburettors, only the very first M-105 and M-105P versions had float type carburettors that would cut out under negative Gs.
|John Rist, 14.10.2010|
Does anyone know of a source for paint colors for the La-5. The model I am building is the 'White 60' Colors are AMT-4,-6, and -7
|Stewart Graham, 25.06.2010|
Does anyone know if the plans available for these aircraft?
Hats off to the Lavochkin fighters, La-5FN and -7!
I like the ruggedness of radial powered fighters and these had fuel injection from 1943. So, they could do a negative g dive. How many Yaks could match that?
Maybe the Yak-9U but the new engine wasn't as reliable.
It was armed with more than 1 fast cannon (of a Yak) and it could also fly circles around Luftwaffe fighters just like the Yak. Would be interesting to see how it did against the IJAAF at the end of the war.
It's only weaknesses would be at high altitude and maximum range, niether really required where it fought the Luftwaffe.
Which cannons were installed was by availability. Most were twin ShVAK 20mm CN for about 23(x96g) total rps - a bit light. I have to wonder if any ended up with a ShVAK and a VYa!!
You get the left jab and the KO punch! The best of a faster synchronized 20mm CN than most anyone paired with the pure power of the synchronized 23mm CN without peer for 11(x96g) / 6 (x200g) rps. Don't forget - double the HE factor too!
Salvo of fire = 2.467kg/sec. 2 cowl VYa-23 CN (6+ rps each).
These were slow when synchronized but penetrated 1" armor even at ranges between 400 and 1000 meters. Better as a bomber destroyer than a dogfighter. At faster rates of fire (500 rpm) it could jam and gun wear was above average. It outclassed any 20mm CN for punch (200g +10g HE). That couldn't be said of the more reliable ShVAK 20mm CN with a 96 gram projectile.
Salvo of fire = 2.266kg / sec. 2 cowl synchronized ShVAK CN.
Climb to 5km = 4.7 min. (La-5 = 6.0 min.)[-5F = 5.5 min.]
360 turn = 19 sec. (La-5 = 22.6 sec.)[-5F = 20 sec.]
Do you have any comments about this aircraft ?