Difference between revisions of "D3A1"

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|name        =[[Template:Infobox Aircraft/doc|Editing this template]]
 
|name        =[[Template:Infobox Aircraft/doc|Editing this template]]
 
|image        =
 
|image        =
|type        =
+
|type        =Carrier Based Dive Bomber
|variantof    =
+
|variantof    =D3A
|country      =
+
|country      =Japan
|manufacturer =
+
|manufacturer =Aichi
|crew        =
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|crew        =Two
|wingspan    =
+
|wingspan    =47', 2"
|length      =
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|length      =33', 5"
|height      =
+
|height      =12', 8"
 
|internalfuel =
 
|internalfuel =
 
}}
 
}}
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===Development===
 
===Development===
 +
In mid-1936 the Japanese Navy issued the 11-Shi specification for a monoplane carrier-based dive-bomber to replace the existing D1A biplanes currently in service. Aichi, Nakajima and Mitsubishi all submitted designs, and Aichi and Nakajima were both asked for two prototypes each.
  
 +
The Aichi design started with low-mounted elliptical wings inspired by the Heinkel He 70 Blitz. The fuselage looked quite similar to the Zero, although the entire plane was built stronger to withstand the rigours of dive bombing. It flew slowly enough that the drag from the landing gear was not a serious issue, so fixed gear were used for simplicity. The plane was to be powered by the 710 hp (529 kW) Nakajima Hikari 1 nine-cylinder radial engine.
 +
 +
The first prototype was completed in December 1937, and flight trials began a month later. Initial tests were disappointing. The aircraft was underpowered and suffered from directional instability in wide turns, and in tighter turns it tended to snap roll. The dive brakes vibrated heavily when extended at their design speed of 200 knots (370 km/h), and the Navy was already asking for a faster diving speed of 240 knots (440 km/h).
 +
 +
The second aircraft was extensively modified prior to delivery to try to address the problems. Power was increased by replacing the Hikari with the 840 hp (626 kW) Mitsubishi Kinsei 3 in a redesigned cowling, and the vertical tail was enlarged to help with the directional instability. The wings were slightly larger in span and the outer sections of the leading edges had wash-out to combat the snap rolls, and strengthened dive brakes were fitted. These changes cured all of the problems except the directional instability, and it was enough for the D3A1 to win over the Nakajima D3N1.
  
  
 
===Unit Deployment===
 
===Unit Deployment===
 +
In December 1939 the Navy ordered the aircraft as the Navy Type 99 Carrier Bomber Model 11 (kanjō bakugekiki, usually abbreviated to kanbaku.). The production models featured slightly smaller wings and increased power in the form of the 1,000 hp (746 kW) Kinsei 43 or 1,070 hp (798 kW) Kinsei 44. The directional instability problem was finally cured with the fitting of a long dorsal fin, and the aircraft actually became highly maneuverable.
 +
 +
Armament was two forward-firing 7.7 mm Type 97 machine-guns, and one flexible 7.7 mm Type 92 machine gun in the rear cockpit for defense. Normal bombload was a single 250 kg (550 lb) bomb carried under the fuselage, which was swung out under the propeller on release by a trapeze. Two additional 60 kg (130 lb) bombs could be carried on wing racks located under each wing outboard of the dive brakes.
 +
 +
Starting with the attack on Pearl Harbor, the D3A1 took part in all major Japanese carrier operations in the first ten months of the war. They achieved fame during the Indian Ocean raid in April 1942 when the D3A1s scored with over 80% of their bombs during attacks on the British cruisers HMS Cornwall and HMS Dorsetshire and the carrier HMS Hermes. In some cases they were pressed into duty as fighters, their maneuverability being enough to allow them to survive in this role.
 +
 +
In June 1942, an improved version of the D3A powered by a 1,300 hp (970 kW) Kinsei 54 was tested as the Model 12. The extra power reduced range, so the design was further modified with additional fuel tanks to bring the total tankage to 900 L (240 U.S. gal, giving it the range needed to fight effectively over the Solomon Islands. Known to the Navy as the Model 22, it began to replace the Model 11 in front line units in autumn 1942, and most Model 11s were then sent to training units.
 +
 +
When the Yokosuka D4Y Suisei became available, the D3A2s ended up with land-based units or operating from the smaller carriers, which were too small to handle the fast-landing Suisei. When American forces returned to the Philippines in 1944, land-based D3A2s took part in the fighting but were hopelessly outdated and losses were heavy. By then many D3A1s and D3A2s were operated by training units in Japan, and several were modified with dual controls as Navy Type 99 Bomber Trainer Model 12s (D3A2-K). During the last year of the war the D3A2s were pressed back into combat for kamikaze missions.
  
 +
In 1945, Indonesian guerillas captured numerous ex-Japanese air bases. Several numbers of D3A Val were captured by Indonesian guerillas, including at Bugis Air Base in Malang (repatriated 18 September 1945). Most of the aircraft were destroyed during 1945-1949 when the former Dutch East Indies and the Netherlands were engaged in military conflict/police action in Indonesia.
  
  
 
===External Links===
 
===External Links===
 +
* [http://www.combinedfleet.com/ijna/d3a.htm Aichi D3A, Joao Paulo Julião Matsuura]
 +
* [http://www.airtoaircombat.com/detail.asp?id=267 AirToAirCombat.Com: Aichi D3A Val]
  
 
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|name        =[[Template:Infobox AH Aircraft/doc|D3A1 "Val"]]
 
|name        =[[Template:Infobox AH Aircraft/doc|D3A1 "Val"]]
 
|image        =
 
|image        =
|type        =Bomber
+
|type        =Carrier Based Dive Bomber
|variantof    =  
+
|variantof    =D3A
 
|crew        =Two
 
|crew        =Two
 
|loadout1-1  =2x 7.7mm MG, 1000 rounds/gun
 
|loadout1-1  =2x 7.7mm MG, 1000 rounds/gun

Revision as of 14:01, 9 May 2009

This aircraft page is in two sections:
World War II aircraft
Editing this template
Variant of D3A
Type Carrier Based Dive Bomber
Country of origin Japan
Manufacturer Aichi
Crew Two
Dimensions Wing span 47', 2"
Length 33', 5"
Height 12', 8"
how to edit

The D3A1 in World War II

Development

In mid-1936 the Japanese Navy issued the 11-Shi specification for a monoplane carrier-based dive-bomber to replace the existing D1A biplanes currently in service. Aichi, Nakajima and Mitsubishi all submitted designs, and Aichi and Nakajima were both asked for two prototypes each.

The Aichi design started with low-mounted elliptical wings inspired by the Heinkel He 70 Blitz. The fuselage looked quite similar to the Zero, although the entire plane was built stronger to withstand the rigours of dive bombing. It flew slowly enough that the drag from the landing gear was not a serious issue, so fixed gear were used for simplicity. The plane was to be powered by the 710 hp (529 kW) Nakajima Hikari 1 nine-cylinder radial engine.

The first prototype was completed in December 1937, and flight trials began a month later. Initial tests were disappointing. The aircraft was underpowered and suffered from directional instability in wide turns, and in tighter turns it tended to snap roll. The dive brakes vibrated heavily when extended at their design speed of 200 knots (370 km/h), and the Navy was already asking for a faster diving speed of 240 knots (440 km/h).

The second aircraft was extensively modified prior to delivery to try to address the problems. Power was increased by replacing the Hikari with the 840 hp (626 kW) Mitsubishi Kinsei 3 in a redesigned cowling, and the vertical tail was enlarged to help with the directional instability. The wings were slightly larger in span and the outer sections of the leading edges had wash-out to combat the snap rolls, and strengthened dive brakes were fitted. These changes cured all of the problems except the directional instability, and it was enough for the D3A1 to win over the Nakajima D3N1.


Unit Deployment

In December 1939 the Navy ordered the aircraft as the Navy Type 99 Carrier Bomber Model 11 (kanjō bakugekiki, usually abbreviated to kanbaku.). The production models featured slightly smaller wings and increased power in the form of the 1,000 hp (746 kW) Kinsei 43 or 1,070 hp (798 kW) Kinsei 44. The directional instability problem was finally cured with the fitting of a long dorsal fin, and the aircraft actually became highly maneuverable.

Armament was two forward-firing 7.7 mm Type 97 machine-guns, and one flexible 7.7 mm Type 92 machine gun in the rear cockpit for defense. Normal bombload was a single 250 kg (550 lb) bomb carried under the fuselage, which was swung out under the propeller on release by a trapeze. Two additional 60 kg (130 lb) bombs could be carried on wing racks located under each wing outboard of the dive brakes.

Starting with the attack on Pearl Harbor, the D3A1 took part in all major Japanese carrier operations in the first ten months of the war. They achieved fame during the Indian Ocean raid in April 1942 when the D3A1s scored with over 80% of their bombs during attacks on the British cruisers HMS Cornwall and HMS Dorsetshire and the carrier HMS Hermes. In some cases they were pressed into duty as fighters, their maneuverability being enough to allow them to survive in this role.

In June 1942, an improved version of the D3A powered by a 1,300 hp (970 kW) Kinsei 54 was tested as the Model 12. The extra power reduced range, so the design was further modified with additional fuel tanks to bring the total tankage to 900 L (240 U.S. gal, giving it the range needed to fight effectively over the Solomon Islands. Known to the Navy as the Model 22, it began to replace the Model 11 in front line units in autumn 1942, and most Model 11s were then sent to training units.

When the Yokosuka D4Y Suisei became available, the D3A2s ended up with land-based units or operating from the smaller carriers, which were too small to handle the fast-landing Suisei. When American forces returned to the Philippines in 1944, land-based D3A2s took part in the fighting but were hopelessly outdated and losses were heavy. By then many D3A1s and D3A2s were operated by training units in Japan, and several were modified with dual controls as Navy Type 99 Bomber Trainer Model 12s (D3A2-K). During the last year of the war the D3A2s were pressed back into combat for kamikaze missions.

In 1945, Indonesian guerillas captured numerous ex-Japanese air bases. Several numbers of D3A Val were captured by Indonesian guerillas, including at Bugis Air Base in Malang (repatriated 18 September 1945). Most of the aircraft were destroyed during 1945-1949 when the former Dutch East Indies and the Netherlands were engaged in military conflict/police action in Indonesia.


External Links

Aces High II aircraft
D3A1 "Val"
Variant of D3A
Type Carrier Based Dive Bomber
Crew Two
Aces High II loadout options
Package 1 2x 7.7mm MG, 1000 rounds/gun
1x 7.7mm MG in rear cockpit, 791 rounds
Options 1x 250kg bomb
2x 50kg bombs
Aces High II Main Arenas
Earliest MA Early War
Typical perk cost 0 (Late War)
ENY value 40 (Late War)
Available on carrier yes
how to edit

The D3A1 in Aces High II

A Japanese dive-bomber, the Val is often the sort of opponent most fighter pilots dream about. Slow and basically unarmed, an easy kill if poorly piloted with little hope of defending itself. AH reality can be very different though as the Val is exceptionally maneuverable at almost ludicrously low speed. A good Val pilot can actually be a very elusive and frustrating target that requires patience and skill to defeat. A few pilots have even taken this to the extreme, using the Val like bait to attrack unwary opponents, only to allow other fighters to jump on the helpless victims that are solely focused on the Val. Many a pilot has been caught in that trap.

Engine Power

Pathetic, sea-level cruising speed is only 219mph while adding the centerline bomb will reduce that to 214mph. Increasing altitude helps a little though 240mph at 9K is barely worth mention, but speed holds fairly solid up through 20K. Acceleration feels very sluggish to top speed but not too bad at low speed, especially if you don't have a bomb aboard. Climb rate is low at 2,300ft/min although that isn't terrible. Fuel range is a very respectable 82minutes but your total range is still poor considering your low cruise speed. The Val does have fixed landing gear though so considering the wheels are out dragging in the wind the numbers aren't that surprising.


Aces High II Performance Charts

D3A1 speed chart D3A1 climb chart

Firepower

Very light, the Val doesn't really have the means to attack anything or protect itself with guns. There are a pair of forward mounted 7.7mm guns with 1,000 rounds/gun mounted in the cowling and a single flexibly mounted 7.7mm with 791 rounds that helps protect your tail. Both are basically hopelessly outclassed in the game. Even if you manage to get someone in front of you so you can shoot your forward guns, expect them to take a long time to be effective. To the rear, the most likely avenue for enemy attack, the single 7.7mm is even worse, don't rely on it as any defense and never man it to attempt to defend rather than maneuver. Of course, this is a dive-bomber though and you would expect a large bombload but that isn't the case. A centerline mounted 250kg bomb (~510lbs) is reasonably sized but not up to the large load carrying of other aircraft. You also can load a pair of 50kg bombs on the wings but these are small and only effective against light structures. There is an interesting dive-bombing sight that can be used to refine your aim although I have yet to figure out how to use it successfully, consistently.


Maneuverability

The Val is maneuverable to the point of being insane. A low speeds, and we are talking VERY low, it can turn like a kite, humiliating some fighters as it flips around the sky. Even at high speeds, with a caveat or two, it remains totally controllable right through 520+mph. Roll-rate is always reasonable and the dive performance is quite good although not recommended in a defensive position. If you are free of bombs then I don't know if anything can actually turn with you other than maybe a Zero, but even it might not be a clear victor. Collisions and overshoots are always a concern as many aircraft will stall or plow right through a Val at the speeds it typically flies at. On concern with speed is the fraiglity of the landing gear, with airframe over-stress starting around 425mph and the actual landing gear tearing off at only 480mph. While having no impact on handling (possibly even improving it), the gear do certiainly offer advantages when landing vs. belly landings.


Fighting in the D3A1

Why? That's the question you should ask yourself before taking a Val out for a spin other than in a scenario. The firepower it offers is simply so sub-standard that it is not worth the hassle to fly it. Also, there is a real "easy-kill" mentality in the MA where people will basically suicde to make what they feel is a sure, or important, kill. Usually a Val will attract as much attention as a perk plane in that fashion.

Offensively, the Val could be used in local defense against vehicles quite effectively or as a light strike aircraft where you have control of the sky. I wouldn't intend on fighting with a Val in a really tight spot where you are out-numbered. That said, the Val works as great bait to set people up to be killed by other aircraft which is great fun. You can use the Val is a decent turn-fighter, it appears to be a significantly tougher than the Zero and seems to turn just as well if not better at very low speeds. In a stall fight you will humiliate against most aircraft in turn-rate and barely be trying. Look for overshoots that you can exploit and always watch yourself so you aren't predictable in defense. You will be using a lot of break turns so be ready to mix up the directions and angles to keep the enemy guessing. If you can, lock onto someones tail and chip away with the 7.7mm's, you can either scare them off or cause them to crash if they overmaneuver their aircraft. All of my kills in a Val have been to stalling Spitfires and such who, rather than simply straighten out and run away, instead try to turn just a little harder, lose control and crash.

Defensively, be very alert and throw every strange and unexpected maneuver you can into your defense. You will be using a lot of break turns to avoid enemies coming from the rear so be good with your timing and make them very sharp and hard. Slow aircraft are vulnerable if caught un-aware or in slow moving crossing shots. Those are easy situations so you want to make sure you don't give them up. The Val is not very tough, it can not take hardly any damage to larger calibre weapons without breaking to pieces. Nothing, other than maybe a Zero, can out-turn you at low speeds. Most enemy aircraft will attack, extend, and then re-engage though to avoid any possibility of falling into a trap. Look for overshoot potential to pounce and strike back with your cowl guns. If you can, try and enlist a gunner for your rear as the combination of a rear gunner and someone who is maneuvering hard to avoid attacks can be very difficult to beat. The rear gunner may land some lucky hits and kill, or damage, and enemy fighter.

A few last notes, the Val works well at low altitude, sometimes very low. The landing gear, because it is always extended, can actually help you in some maneuvers like looping near the ground. I've had enemy aircraft crash trying to follow my low loops even though my own aircraft brushed the ground but the landing gear bounced me back into the air without damaging my aircraft. I know, it's a crazy tactic, but sometimes it's things like this that can save your butt and cause the frustration of many enemy pilots who attempt to follow and smack the ground (giving up proximity kills).


Fighting against the D3A1

Don't turn-fight and don't be all that worried about it's offensive potential. You need to properly predict where it will turn (they always turn) and place your gunsight in that location waiting to intercept them early in their break-turn. Don't slow down and turn-fight one, it's a losing proposition. Attack extend even if only a short distance, then re-attack, over and over until you make the kill. Just try and land some hits, the Val is not tough and can easily be shot to pieces with smaller calibre weapons. Vertical attacks, like a BnZ, should be almost impossible for a Val to counter unless it can get you looping slowly. If necessary, use a Head-On, it is unlikely the Val can apply more than token damage to you with it's pathetic cowl guns.

If a Val gets behind you then simply extend, jinking, or roll, just a bit to make the Val have a tougher aiming issue. That is as much to make the shots miss as to spread them out so they don't concentrate in any one area. The likelihood of a single bullet critical hit is very remote but you don't want hits to add up in any one area. Vals tend to be very aggressive as they have few options for retreat so be prepared for them to come right after you if they can. Quick rolling direction changes can work well as the Val has a large wingspan and momentum is a bit of a problem.

A final thought, usually when something like a Val flys into an area it attracts a lot of attention as everyone knows it is a pretty defenseless kill. This means a lot of friendly fighters are likely to stop whatever they are doing in order to try and jump the Val and get the kill quickly. This can lead to a large number of friendly aircraft in close proximity and creates a situation where killshooter is a problem. Don't get too greedy, watch for other enemies in the area, and leave the Val if it looks like you won't be able to shoot it down before more bogies arrive.


External Links

Soda's Aircraft Evaluations