Correct Identification of IL-2 Wing Types


Despite the publication of some extremely fine IL-2 scale drawings in Kagero's No 13 title on the aircraft, there seems to remain considerable difficulty across various readerships to identify the type of wing in view in any given photograph. That is to say, are we looking at a straight-winged two seat machine, or an 'arrow' (swept-wing version)? The author wonders why this should be the case? Therefore, the intention of this guide is point out some of the obvious differences in features and geometry of the two wing designs, and thus assist in the correct identification of these aircraft.

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IL-2 Wing Basic Geometry


The "straight" Il-2 wing is in fact not aligned exactly to the inner wing section's Leading nor Trailing Edge (LE nor TE). The outer wing panel on the straight wing is swept back 5 degs at the LE and 3.5 degs at the TE. This geometry is specified exactly in the Teknicheskoe Opisane (Technical Manual). Such small angles are often difficult to see from the various camera positions in photographs, and in some cases these details simply cannot be seen.

However, if one may find the sight-line for the inner wing section trailing edge, then that may be elaborated to reveal the wing type: a line drawn along the inner wing section TE will meet the wing tip approximately in line with the middle of the aileron edge. Likewise, if the wing outer section's LE sight-line can be seen, this will intersect the fuselage side approximately at the aft end of exhaust stack #5. If both wing tip navigation lights can be seen (from mostly above), a line between them will agree with the aft edge of the main (front) armour-glass windscreen.

The size and position of the pitot tube on the starboard wing is another excellent indicator. A straight wing pitot tube will usually be shorter (there are some exceptions, but these are rare) and will always be mounted further inboard than the pitot on an 'arrow' wing [see below].

The 'arrow' (so strelkoi) wing features a much larger angle of intersection, both at the Leading and Trailing Edge.
The outer wing panel on the arrow wing is swept back 15 degs at the LE and 8.5 degs at the TE. This geometry is specified exactly in the Teknicheskoe Opisane (Technical Manual). The "bend" or intersection of the LE/TE is pronounced, and observers should find that in most cases these will be apparent in photographs of the Il-2.

If the sight-line for the inner wing's TE can be seen, this is again quite instructive for identification purposes:
a line drawn along the inner wing section TE will meet the wing tip essentially at the middle, well ahead of the aileron. If the wing outer section's LE sight-line can be seen, this will intersect the fuselage side approximately at the aft end of exhaust stack #4. If both wing tip navigation lights can be seen (from mostly above), a line between them will agree with the joint between the windscreen and the canopy.

As mentioned,
an arrow wing pitot tube will usually be longer and will always be mounted further outboard than the pitot on a straight wing.

Another outstanding identification feature between the two wing types are the flaps. If the flaps are in view-- or the aft wing under-surface in general-- it is usually the case that an absolute determination can be made.

On the straight wing [left], the flap edge is in line with the aileron. On the arrow wing [right], it is not in line. If this feature is in view, identification is unequivocal and the discussion of wing type is closed.


Practical Examples

Photographic analysis is difficult for many with respect to various aspects of an aircraft's appearance, version or technical details. Even so, practice and the study of many Il-2 photos should help any observer to refine their identification abilities. The following examples should serve to help pick out key areas of recognition with regards to the Shturmovik's wing type.


Our well known friend, "White 28". Here the wing type is fairly clear and straightforward: a small angle of intersection along both the LE and TE, sight-line along the inner wing aft TE intersects the wing approximately mid-aileron chord. STRAIGHT WING.


"White 66" showing identical features:
small angle of intersection along both the LE and TE, sight-line along the inner wing aft TE intersects the wing approximately mid-aileron chord. Further, the navigation light to starboard can almost be seen. A line drawn from the port lamp to the starboard's approximate location (or indeed to "White 11's" port lamp, which is quite well aligned) passes along the aft end of the front armour-glass plate. STRAIGHT WING.


"Red 7", seen most instructively from below. In this view the flap is utterly clear and there is no ambiguity.
STRAIGHT WING.


In this image the LE of the wing simply cannot be seen, due both to the visual angle and also the harsh shading. However, a keen observer will spot the pitot tube to starboard which is clearly long in size and outboard in placement. ARROW WING.


Another very difficult viewing angle on this delightful example with a dedication to Oleg Koshevii. With the greatest luck, however, the TE of the flap is just illuminated in the photo, allowing us to trace its position. It does not agree with the aileron's alignment.
ARROW WING.


Good old "White 94". The viewing angle is tricky, yes, but even so when extending the sight-line of the inner wing section's TE we see it encounters the wing tip near the aileron.
STRAIGHT WING.


The relatively large angle of intersection along the inner and outer wings' LE is clear. Also, the pitot can just be seen, and although the length is cropped the placement is certainly outboard.
ARROW WING.


Here we see virtually no angle of intersection along the wing's LE. Better versions of this photo also reveal a short, inboard positioned pitot tube.
STRAIGHT WING.


The rather famous Mstitel', or "White 25", over Germany. A dramatic angle of intersection is clear along the wing LE, and also just visible on the TE. The inner wing's TE sight-line can be elaborated and it encounters the wing tip at mid-point, well ahead of the aileron.
ARROW WING.


"Chapaevtsy" as seen in a nice line-up. Once more the inner wing TE sight-line can be extended, and this encounters the wing at the mid-point. The large and outboard positioned pitot tube is also in view.
ARROW WING.


Modelling Madness

We have seen, alas, some cases of persistently poor Il-2 identification in scale model kits and on Il-2 decal sheets. Many have been the requests to address these cases one-by-one, but that might be a larger undertaking than we have room for here. However, let's take a brief look in any event at some of the more pressing errors of this type.

HSU Pavlov's "White 1"
Surely the most disastrous of all failed identifications, this one leaves the author a bit speechless. Many good quality photos exist and have been published of this machine. It is a clear-- unmistakable-- case of a straight, wooden winged Il-2. Despite this fact, we have seen it represented on various kit box tops as an arrow, even a metal winged arrow (!), and moreover finished in NKAP style camouflage! The aircraft was photographed before arrows existed, which should have ended that idea from the start. It was also photographed before the Il-2 NKAP templates were released, and built well before even that, and is clearly wearing a two-colour scheme, not three! Honestly, the lack of understanding on display here is worrying.
STRAIGHT WING.


"White 07" Za Leningrad, 566 ShAP
This aircraft has been depicted on decal sheets both as a straight wing and arrow model. The long outboard pitot and flap arrangement are both in view-- it is an ARROW WING.

"White 100" 7 GvShAP (possibly belonging to VB Eremalenko)
The TE of the inner and outer wing intersection is clearly in view with a minimal angle difference.The flap can also be seen and agrees with the aileron orientation.
STRAIGHT WING.

"V" Aleksandr Suvorov of VT Aleksukhin, 617 ShAP
Aleksukhin was sadly killed in December 1943, before the appearance of the arrow model.
STRAIGHT WING.

"White 94" of GM Parshin, 943 ShAP
This example is shown above, with explanation.
STRAIGHT WING.


Hopefully these specific cases will serve as examples to those wishing to identify IL-2 wings. Careful observation and bearing in mind the basic geometries of the wings as described above should assist the observer to work out the correct version in most photographs. Extreme care should be exercised, as demonstrated here, when referring to any existing profile artwork, illustration, modelling reference or other related source as to the identity and type of any Il-2 aircraft. Inevitably there will be some images where no determination is posible, but certainly those examples should be very much in the minority.


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