Why British Tanks Used the Sun as a Weapon D

At 0540 on December 9th, 1940, in the flat gravel desert west of city Bani, Egypt, a column of Matilda II infantry tanks rolled forward directly out of the rising sun. Their armor was thick, but their guns were weak, a two-pounder that could barely trouble a fortified position on a hole that made 8 mph flat out.

Italian gunners of the 10th Army, dug into concrete imp placements with modern Canon Day 4732 anti-tank guns, had every reason to expect an easy morning. On paper, this shouldn’t have worked. The Matildas had no smoke dischargers worth mentioning, no air support yet overhead, and were attacking prepared positions in daylight. The single scenario every inter war tank doctrine manual said to avoid.

Yet within 3 hours, the city Barani camps had collapsed, and over 38,000 Italian soldiers were marched into captivity for a cost. The British Western Desert Force could measure in dozens, not thousands. The tanks hadn’t outguned the defenders. They had made the defenders unable to see them coming, using a weapon that cost nothing, needed no factory, and never ran out of ammunition, the sun itself.

Standard military thinking in 1940 treated timing as a matter of surprise and logistics. Attack before dawn, before the enemy has stood to before reconnaissance aircraft are up. Italian and later German gunnery doctrine assumed that once daylight broke, visibility favored the defender, who was static, ranged in, and dug in behind pre-measured killing zones.

Critics of Desert Armor, and there were many in the British general staff itself, argued that tanks moving in daylight against implaced anti-tank guns were simply offering themselves as targets. The German 88 dele or flat gun, repurposed as a tank killer, could hit a Crusader or Matilda at ranges beyond 1800 meters, well before the tank’s own two-pounder or later six pounder could reply effectively.

On specifications alone, this was correct. A Matilda II’s QF2 pounder had an effective range against armor of roughly 500 meters. German 80 millilium rounds were killing tanks from more than three times that distance. Every table of comparative penetration and range said the desert belonged to whoever saw first and fired first.

What actually mattered was that seeing first meant nothing if you were staring into a molten white disc low on the horizon. The desert sun at latitude 31° north rises and sets almost flat along the horizon for a longer stretch than it does in temperate Europe. And the flat gravel plains of the western desert offered no ridge lines, no trees, no terrain features to break the glare or throw shadow.

British commanders, first informally among cavalry regiment officers who had spent peace time years training in Egypt and later as deliberate staff planning, worked out that an attack launched so the sun sat directly behind the advancing armor turned every German or Italian optical site into a source of pain rather than information.

Anti-tank gun layers using the ZF308 telescopic site standard on German 50 millimeters and 80 millimeter guns found the image washed out to blinding white the moment they tracked a target silhouetted against the rising sun. Range finding became guesswork and guesswork at 1800 meters is worse than no shot at all.

The secret was in the choreography, not the hardware. Commanders synchronized start lines and H hour, not around when infantry could move safely, but around the precise minute the sun cleared the horizon enough to blind without yet being high enough to lose its horizontal eyele glare. That window in the western desert in December lasted perhaps 40 minutes.

The proof came again and again as the desert campaign matured. During Operation Compass, follow-on actions at Bukbuk and Safi on December 10th 11th, 1940, British 7th Armored Division deliberately routed attacking columns so that Italian gun crews at Point 90 and the surrounding perimeter defenses faced directly east into full sunrise.

Afteraction reports from the seventh Hosars noted Italian battery fire falling consistently short and wide during the first half hour of contact. Correcting only once the sun had climbed higher and lost its horizontal blinding angle, by which point British armor had already closed to effective range.

Captured Italian artillery officers, when interrogated, repeatedly described the same problem. They could see the dust cloud and hear engines, but could not resolve individual tank silhouettes against the glare long enough to lay a gun accurately. The pattern repeated at the battle of Betafam in February 1941 where seventh armored divisions flanking Dash across the desert to cut off the retreating Italian 10th Army again used early morning positioning to blind Italian rear guard anti-tank crews at the moment of contact, a factor Major General Michael Omore Moore. Ka’s own staff cited when explaining how tank losses stayed under 20 vehicles against an entrenched force many times the attackers’s size. The tactic became formalized enough that by the time of the second battle of El Alamneagne in October November 1942, timing tables issued to armored brigade commanders cross referenced not just German minefield surveys and artillery fire plans but sunrise and sunset tables for the specific latitude and date printed alongside ammunition aotments. British tank crews of the ninth armored brigade

in their costly but decisive dawn assault on the German gun line at Tel Aakir on November 2nd 1942 moved forward with the rising sun behind them directly into a screen of German 80 mm and 50 mm anti-tank guns. German gunners of the Africa Corps and reports gathered afterward by British intelligence officers described losing visual track of Sherman and Crusader silhouettes for critical seconds at exactly the ranges thousand to 1500 meters where their guns held the theoretical advantage.

One German anti-tank crew survivor questioned by a British intelligence officer after being taken prisoner near the Raman track put it simply, “We could hear them before we could aim at them, and by the time we could aim, they were already too close for it to matter. The brigade lost heavily to mines and to guns that did find their mark once the light equalized.

Some 75 of 94 tanks damaged or destroyed by the actions end, but it broke the gunline, and the survivors did so specifically because the first decisive minutes of contact had been fought with German optics staring into blinding light. This wasn’t an accident of geography that British commanders simply noticed and exploited once.

It was trained doctrine passed down through the desert experienced regiments and eventually written into pre- battle planning as rigorously as fuel consumption or wireless frequencies. Commanders weren’t clinging to some romantic cavalry notion of rioting at the enemy with the sun at your back. They understood with cold technical precision that every optical sighting system fielded by Axis anti-tank and artillery units in North Africa depended on a gunner’s naked eye resolving a target through a narrow field telescopic sight. and that a naked eye pointed at a rising or setting sun physically cannot resolve fine detail regardless of training or equipment quality. No amount of German optical engineering and German gun sites were by most contemporary assessments superior in clarity and codings to their British equivalents could compensate for a gunner’s pupil being flooded with direct sunlight. What looked in staff college exercises and peacetime gunnery trials conducted under even overcast conditions like a straightforward contest of range and penetration turned out in the actual

desert to be a contest partly decided before either side fired a shot by whoever had arranged the compass bearing of the attack. This wasn’t a matter of German gunnery being inferior. German anti-tank crews in the desert were by both British and their own afteraction assessments extremely effective once conditions were even routinely destroying tanks at ranges British guns couldn’t match.

They were right about the mathematics of penetration in range. They were wrong to assume the desert offered a level field on which those numbers alone decided the fight. Battlefields aren’t gunnery ranges with fixed lighting and known bearings. They are three-dimensional problems where a low, flat, dust-hazed horizon and a punishingly bright sun were as real and exploitable a feature of the terrain as any ridge or wadi.

British desert veterans, many of whom had spent peaceime years training and soldiering in Egypt and Palestine before the war, understood the desert’s light in a way that formal armor doctrine written largely in temperate Europe, had never accounted for. There was a second, quieter piece of the puzzle that made the tactic more than a lucky coincidence of geography. Dust.

Desert soil in the western desert is fine, powdery, and easily thrown up by tank tracks and wheeled vehicles. And a column, advancing at speed, generates a haze that hangs almost motionless in the still early morning air. On its own, dust is usually treated as a liability. It gives away a column’s position from miles off and can choke engines and optics alike.

But combined with a low sun directly behind the attacker, that same dust became an additional filter, scattering and diffusing the light even further and turning the horizon into an indistinct shimmering wall of white glare rather than a clean line against which individual vehicles could be picked out.

German gunners who might on a still dust-free morning eventually have adjusted their aim as the sun climbed a few degrees instead found their sight lines degraded twice over. First by direct glare, then by the haze thrown up by the very tanks they were trying to track. British armored regiments learned to read this interaction closely.

Too little dust and the enemy adjusted too quickly. Correctly timed, a fast-moving column at dawn generated exactly enough haze to extend the blinding window by several extra minutes. Often the minutes that decided whether a gun crew got a clean shot at one 200 m or only a hurried wide one at 400. Training reflected this.

Regiments rotating through desert postings before and during the war ran dawn and dusk gunnery and driving exercises specifically to build the habit of judging the sun’s angle in the resulting glare cone. A skill that had no equivalent in the temperate ranges of Salsbury plane or Bovington where British armored doctrine had originally been written.

Troop leaders were taught to check not just map bearings and objective lines, but the almanac, sunrise, and sunset times for the exact date and latitude, cross referenced against the compass bearing of the planned axis of advance. A start line drawn 5° off the ideal bearing could mean the difference between attacking with the sun square behind the column and attacking at an oblique angle that let defending gunners see clearly around the glare within minutes rather than tens of minutes.

This was not folklore passed between veteran troop sergeants, though it certainly circulated that way, too. By 1942, it had been formalized enough that some planning staffs distributed simple sun angle diagrams alongside minefield maps and artillery fire plans, treating the sun as seriously as any other terrain feature an attack had to be built around.

What made the tactic work wasn’t any single technical feature of the tanks themselves. The Matilda’s thick armor helped it survive the approach, and the Crusader’s speed helped it close distance quickly. But neither quality mattered without the timing. What mattered was that a commander with a sunrise table, a compass, and the discipline to hold his start line for the right 40-minute window could turn a technologically inferior tank force into the side that saw clearly while the other side didn’t. The lesson British armored commanders drew from City Bari through Lamagne wasn’t about tanks at all. It was that in combat, the side that wins is often not the side with the better numbers on a specification sheet, but the side that understands which of the battlefield’s ordinary, unglamorous features, light, dust, ground, weather, can be turned from background scenery into a weapon nobody has to manufacture, requisition, or maintain because it rises over the horizon for free every single Morning.