A Historical View Of Air Policing Doctrine: Lessons From The British Experience Between The Wars, 1919-1939

By Michael A. Longoria

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Testing Air Policing In Somaliland

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Michael A. Longoria

Air University Press (1992)



Testing Air Policing In Somaliland

Testing Air Policing In Somaliland
Map of British Somaliland in 1920, showing the route taken by the Somaliland Camel Corps during the campaign of 1920. Source: Pinterest

The 1920 air control campaign in Somaliland was a significant turning point in the history of Imperial Policing. It was the first time airpower rather than land forces was used in a primary role. Trenchard seized an opportunity and used the Somaliland experience as proof that airpower could substitute for ground power, and could do so at a significantly reduced cost.[1]

Yet, along with air control’s uniqueness came the realization that the doctrinal precepts guiding airpower’s use were not necessarily revolutionary. As is often the case with activities on the margin of change, there was a part that was old and there was a part that was new.

Accordingly, the questions associated with doctrine have particular relevance. What were the most current notions of doctrine at the time of the campaign? How was the campaign an agent for change and how did the change manifest itself? But before answering these questions, it is necessary to review the history of British involvement in the area.


The 1920 air campaign was the final chapter in the Dervish uprisings which had begun at the turn of the century at the fanatical behest of Sayyid Muhammad Abdille Hassan.[2] For Great Britain, it had been a conflict waged beyond the practical costs of her secondary interests.

Somaliland was somewhat important because it supplied Aden with beef and Aden was more important because it was on the short route to India.[3] But for the Dervish, it ended the life of the man responsible for their movement.[4] The Dervish viewed Abdille Hassan as a holy savior of sorts, but to the British, he was affectionately known as the Mad Mullah. The British campaigns against Abdille Hassan extend from 1899 and the Dervish insurgence to his death in 1920.

The clash between the Christian and Muslim faiths appears to be the root of the problem. Abdille Hassan belonged to the Salihiya Order that had a messianic mission to restore to the Somalis an extreme devotion in the Muslim faith.[5] This brought him into conflict with both the British and his fellow countrymen who followed the established Qadiriya Order. Abdille Hassan believed that Christian colonization had sought to destroy his people’s Muslim faith. This fired his patriotism and he intensified his efforts to win support for the Salihiya, preaching in the mosques and streets that his country was in danger, and urging his compatriots to remove the English ’infidels’ and their missionaries.[6]

After preaching this message around the countryside, Hassan began to accumulate a following. Sometime after April 1899, he commanded a force of over 5,000 men.[7] Subsequently, he declared a jihad against the British and Ethiopians. His followers became known as Dervishes because the term described the acceptance of the Salihiya Order.[8] I.M. Lewis in A Modern History of Somalia has aptly narrowed the window of origin even further.

On 1 September 1899, the British Consul-General for the coast received a letter from the Sayyid accusing the British of oppressing Islam and denouncing those who obeyed or co-operated with the Administration as liars and slanderers. The letter also contained the challenge: ’Now choose for yourselves. If you want war, we accept it; but if you want peace, pay the fine’* The Consul-General replied by proclaiming Sayyid Muhammad a rebel, and urged his government in London to prepare an expedition against the Dervishes. Thus the opening moves in the long-drawn-out conflict were completed…[9]

For twenty years British soldiers chased, fought, and blockaded the Mullah’s religious infantry across the mountains and plains between the British and Italian Somali Protectorates and Ethiopia. These campaigns cost Great Britain a great deal in financial resources and were moderately costly to human lives. The four land campaigns against the Mullah from 1900-to 1905 accounted for over 400 British deaths and over a thousand Levies deaths at a cost of over £3 million.[10]

The story does not, however, end in 1905. Intermittent periods of peace and reconciliation were marred by successive land campaigns against the Mullah for the fifteen years that followed and it was not until the 1920 air campaign that the Dervish insurgency finally came to an end.[11]

Testing Air Policing In Somaliland
De Havilland D.H.9s of the RAF’s Z Unit line up for a mission against Mohammed bin Abdullah Hassan, who had defied British colonial authorities in Somaliland for two decades.

The Campaigns Against Sayyid Muhammad Abdille Hassan

The punitive land expeditions from 1900 to 1905 against Abdille Hassan, each failed to achieve a decisive result. Cumulatively, however, they resulted in a peace accord that gradually withered away into further conflict by 1908.[12] The first of these land campaigns began on 22 May 1901 under the command of Lt-Colonel E. J. E. Swayne.[13] A British expeditionary force consisting mainly of Somali levies set out from Burao to bring the Mad Mullah to justice.

Towards the end of the campaign, however, the mixed British force was ambushed and over 100 friendlies were killed.[14] Colonel Swayne soon gave up his pursuit and returned to Burao. The campaign had succeeded only in temporarily pushing the Mullah out of British territory.[15]

Major-General Sir Charles Egerton commanded the second campaign and the stakes were raised. His expedition grew from 1,500 to 7,000 men.[16] The chase continued with numerous engagements. In one battle fought at Jid Ali over a thousand Dervishes were killed compared to only fifty-eight British losses.[17] But in another engagement, the Dervishes ambushed the British at Gumburu Hill and sustained only minor casualties against 198 British losses.[18]

There was still no decisive result since the Mullah habitually took refuge outside Somali territory. More campaigns followed with the same result. The pattern for the campaigns remained consistent throughout the period and remarkably it was true for the 1920 air control campaign as well.

An Old Doctrinal Basis

The Somaliland air campaign is an important landmark because it takes place on the margin of change. Two reasons support this preliminary conclusion. First, the doctrinal basis for the Somaliland air campaign can be found in the land campaigns that preceded it, and secondly, the uniqueness of the new air weapon caused air planners to consider new types of problems from both a deployment and an employment perspective. Something old and something new–the pattern appears to remain the same even though the weapon changes.

Punitive land campaigns followed a rather logical sequence of events. They each had a similar pattern that began with an exigency; some events caused the government to want action against an alleged perpetrator. Next, depending on the significance of the grievous act, an expedition was organized and launched with the expressed mission of bringing the perpetrator to justice. The political call for help followed.

Next, the organizing of a campaign began and military plans were set in motion: the deployment. The chase began upon arrival in the territory and proceeded in the pursuit of the perpetrator. Time passed and depending on numerous circumstances, the campaign would come to some kind of close. The planning assumptions for the 1920 Somaliland air campaign are consistent with the established pattern.

In 1919 the Cabinet decided to try the new air arm. Group-Captain R. Gordon was placed in command and he immediately set about organizing for deployment.[19] The planning assumptions were for a six-month expedition as a self-contained operation. The greatest care was also given to secrecy. Group-Captain Gordon named the unit by symbol primarily for the secrecy requirement and thus the designation Z unit was given to the force.[20]

In the early deployment stages, it is clear that there was really little difference between the use of air or ground forces. There were some notable exceptions owing to the uniqueness of the airplane.

For example, there was no standard way of deploying aircraft at the time, consequently, everything had to be thought out and implemented with no base of experience. Replacement parts, fuels, lubricants, ammunition, tools not to mention living facilities, medical supplies, food, water storage–all of it and more, some 800 tons worth, had to be packed on the H.M.S. Ark Royal.[21] But in general, this differed little from the deployment requirements of ground expeditions.

Employment Considerations

The air campaign began in earnest on 21 January 1920 with the attack of six aircraft on the Mullah’s command locations at Jid Ali Fort and Medishi Fort. The first raid almost finished the war, as it was afterwards learned that a bomb dropped on Medishi Fort killed one of the amirs who supported Sayyid at the time, and the mullah’s own clothing was singed.[22]

Subsequently, more air raids were conducted during the two days that followed until an air reconnaissance aircraft reported the encampment areas were completely deserted. After this first phase, the Somaliland Field Force, consisting of detachments from the King’s African Rifles, the Somaliland Camel Corps, and the 101st Grenadiers (Indian Army) set about to chase the Mullah.

Air Force operations turned into support for the Army, which consisted largely of keeping in touch with the various detachments, message dropping, and the conveying of dispatches between maneuvering elements. The field force soon occupied the Jid Ali Fort area and learned that the Mullah was heading south toward his stronghold at Tale. Both the field force and air force pursued.

An advance airbase was moved to El Afweina, and on January 31st the Mullah’s caravan was located and bombed from the air.[23] Air bombing was then directed at the Tale Fort as the field force closed in.

The intention at this stage was to allow the ground forces to close in on Tale after further bombing attacks. The latter, however, were rendered unnecessary, as the friendlies intercepted the mullah’s convoy and rushed and captured Tale, while the Camel Corps, in a magnificent pursuit, caught and destroyed the mullah’s personal following which had escaped the fortress.[24]

The operations had been termed a success even though the mullah had escaped across the border because his prestige was destroyed. The operations soon concluded, and all aircraft moved from their forward locations back to Berbera. The field force only temporarily held the Tale Fort region, since with the mullah gone there was no cause for a continued presence. The mullah fled south and settled in Imi where he eventually died of influenza.

From this chain of operational events, it is clear that aircraft were used to conduct the same kind of chase operations that were consistent in most land campaigns. Indeed, in many instances bombing was delayed due to the wait for occupation forces. Ground campaigns were sequentially focused on occupation areas. This was certainly true for Somaliland as well. The campaign was obviously a cooperative measure between air and ground forces.

In the debate that followed, each force would see in Somaliland what it wanted to see.[25] John Salmond argued that the actions of the ground troops were invaluable but subsidiary to the bombing campaign. Henry Rawlinson (the C-in-C India) pointed out that independent air action had lasted just a few days and considered the ground pursuit the most important aspect of the overall campaign. An analysis of the tactical lessons of the campaign may help in sorting out what was old and from what was new.

Testing Air Policing In Somaliland
Open cockpit de Havilland DH9a Bomber. UK Crown Copyright / MOD. Courtesy of Air Historical Branch.

The Cause for Revision

Accepting the fact that the Somaliland air campaign looked a lot like a land campaign, there was a great deal learned about employing the new air weapon. The primary lesson of the campaign was that the deep and persistent attack on a warring tribe created significant operational advantages. The bombing of Fort Jid Ali started a chain of events that led to a successful occupation of the area as well as a more effective chase of the perpetrator.

The air campaign started the ball rolling. In the past ground forces would first have to maneuver into position and begin an engagement before the enemy was required to react; bombing changed that paradigm. Unfortunately, the official codification of this new lesson would be wrapped up in the bureaucratic struggles between the War Office and the Air Ministry, resulting in an often exaggerated view of the facts.

One of the most representative analyses of the time comes from John Slessor’s accounts of the difference between the two methods of dealing with campaigning. It adopts the more exaggerated view of Somaliland.

Now, when the situation reaches a point where it can no longer be handled by political or police action, there are only two alternatives methods of dealing with it, which I shall call the Ground Method and the Air Method. The Ground Method is that traditionally employed by the Army for many years and was indeed the only one in the days before the airplane. It involves the invasion by a column on the ground, a battle with the enemy’s fighting men, and the occupation, sometimes permanent but more often temporary, of his territory.[26]

Slessor’s view of the Ground Method specifically addresses the form of punitive land campaigns, but it neglects to discuss the cooperative measures between land and air forces in joint operations. Naturally, the correct explanation of the Dervish defeat in Somaliland is reasonably somewhere in between those ideas put forth by the Air Ministry and the War Office.

Air attack and cooperation were vitally important, as was the occupation, although temporary, of the Mullah’s many strongholds. The more subtle lessons are however equally important. One of the more critical issues was the manner in which the political dialogue between the Governorship and the warring tribe was affected by air. Leaflet drops and personal visits were the key ingredients in creating this new dialogue.

…the deepest impression was made on the local chiefs by the fact that the Governor of Somaliland was able to visit them and speak to them at the conclusion of the operations, forty-eight hours after the fall of the Mullah’s stronghold. He accomplished the journey from Berbera–300 miles–by air in one day.[27]

Arguably, the most significant impact of the Somaliland air campaign was an acknowledgment of airpower’s ability to deliver an effective but minimum use of force. The ability to reach deep into a tribes’ garrisons and deliver a controlled amount of force and the capacity to improve the dialogue of the governor with the various tribesman by air leaflet drops and direct visits is perhaps the cardinal insight of 1920. Future air policing development would indeed be touched by this crucial lesson.

Summary Hypothesis

Deep attack is proven out by the bombing of Jid Ali; and in large measure, it validates the bombing lesson of Kabul, Afghanistan in 1919. It demonstrated that the airplane could strike beyond the geographical barriers of distance, mountains, deserts, and other various landmasses, even though early technology only allowed for about a 185-mile combat radius.

Cooperation with ground forces was crucial in the overall campaign. If not for the effective occupation of the key mullah strongholds, the air attacks might have had to bomb more to get the same results. Independent air action was not solely proven out in Somaliland. The subtle lessons from Somaliland were more important in the development of air policing tactical doctrine.

Airpower’s inherent flexibility was discovered by enabling the Governor to continue political dialogue during hostile actions. Leaflet drops and personal visits to the warring tribes proved an invaluable part of airpower’s capability. From the first deep attack by DH 9As on Fort Jid Ali to the cooperative missions with the Somali Camel Corps, the origin of air policing tactical doctrine began in Somaliland.

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[1] The Somaliland experience was a contentious issue between the War Office and the Air Ministry. There is a lot of circumstantial evidence that Trenchard used Somaliland as the basis for his arguments for air control to Winston Churchill prior to the Cairo Conference in 1921, especially the cost calculations.

Too much may be made of the R.A.F. effort there, however. John Slessor does not even mention Somaliland in his accounting of the period in The Central Blue. The author agrees with David Omissi in saying that I. M. Lewis offers the most balanced view of the period. Somaliland is used in this essay, not because of its significant proving of airpower, but instead because it offers a clear historical landmark upon which to base a doctrinal evaluation.

[2] David Omissi, Airpower, and Colonial Conflict, The Royal Air Force 1919-1939 (Manchester University Press, 1990), 16.

[3] I.M. Lewis, A Modern History of Somalia, Nation, and State in the Horn of Africa, (London: Longman Group Ltd, 1980), 40.

[4] The term Dervish is used to describe Sayyid Muhammad ’Abdille Hassan’s following–the Salihiya Order of Islam.

[5] I.M. Lewis, A Modern History of Somalia, Nation, and State in the Horn of Africa, 66.

[6] Ibid., 67.

[7] Ibid., 69.

[8] Ibid., 70.

[9] Ibid., * I.M. Lewis cites D. Jardine, The Mad Mullah of Somaliland, London, 1923, 43.

[10] Extrapolated from I.M. Lewis, A Modern History of Somalia, Nation, and State in the Horn of Africa, Chapter IV, 63-91.

[11] Flight-Lieutenant F.A. Skoulding, With ’Z’ Unit in Somaliland, The Royal Air Force Quarterly, 2, no.3, (July 1931): 396. This is the article’s basic conclusion and is subject to the previous arguments against the notion that airpower alone had accomplished the task. The Mullah was not killed by air action. After a handful of near misses, the Mullah fled the country and wandered about for nine months finally settling in Imi on the upper reaches of the Sabelle River in Ethiopia.

According to I.M. Lewis, ’Abdille Hassan died December 1920 at the age of fifty-six from a case of influenza. The Dervish insurgency lost its leader and no successor immediately followed. I.M. Lewis, A Modern History of Somalia, Nation, and State in the Horn of Africa, 80.

[12] I.M. Lewis, A Modern History of Somalia, Nation, and State in the Horn of Africa, 72.

[13] Ibid.

[14] Flight-Lieutenant F.A. Skoulding, With ’Z’ Unit in Somaliland, The Royal Air Force Quarterly, 387.

[15] Ibid.

[16] Ibid.

[17] Ibid.

[18] I.M. Lewis, A Modern History of Somalia, Nation and State in the Horn of Africa, 72.

[19] Flight-Lieutenant F.A. Skoulding, With ’Z’ Unit in Somaliland, The Royal Air Force Quarterly, 388.

[20] Ibid., 390.

[21] Ibid.

[22] Ibid., 392.

[23] Ibid., 393.

[24] Ibid.

[25] David Omissi, Airpower, and Colonial Conflict, The Royal Air Force 1919-1939, 15. Omissi argues that the wider significance of the campaign was a matter for dispute between the services.

[26] John Slessor, The Central Blue, Recollections and Reflections (London: Cassell and Co. Ltd., 1956), 59.

[27] Group-Captain J. A. Chamier, The Use of the Air Force in Replacing Military Garrsions, The Journal of the Royal United Service Institution, 66, no. 462 (May 1921): 212.

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