Tallboy Bomb at The NMS Museum of Regional Traditions

Only until the end of December 2021, fragments of a detonated Tallboy bomb will be on display within "Relics from the Szczecin-Świnoujście Fairway" exhibition, presented at the courtyard of The National Museum in Szczecin – The Museum of Regional Traditions.  

British Tallboy bomb was developed to destroy important strategic targets like German submarine shelters. Adjusted to being dropped from the height of 5500 m at 270 km/h, it was specified as a deeply penetrating bomb. Its explosion created a crater of 24 m in depth and 30 m in diameter. Tallboy was able to destroy a 4.9 m thick layer of concrete. 

Until the end of the war, a squadron of Avro Lancaster bombers, that were adjusted to the use of these bombs (by modification of bomb bay doors and by partial removing of the armour platings and armament in order to reduce the weight), dropped 854 of them, among others, sinking German armored ship named Tirpitz. 

The largest live bomb in Poland was traced underwater in Świnoujście, on September 16th 2019 (at point marked MTL110408) by the Vesna unit, which is part of the SeaTerra fleet. The Sea Terra company was a subcontractor of the consortium implementing works on the DIVO fairway (a joint venture company established by Dredging International and Van Oord). The Tallboy was identified on September 16th 2019 by a team of SeaTerra employees, under the command of the engineering work manager, Eng. Janusz Lemieszek. The Tallboy bomb was found during the investment "Modernization of the Świnoujście - Szczecin fairway to a depth of 12.5 m" carried out by the Maritime Office in Szczecin.

 

The History of Tallboy - Account by Navy Chorąży Michał Jodłoski

The bomb was found during preparatory works before the Szczecin-Świnoujście fairway modernization commissioned by the Maritime Office. The finding was reported to the services of 8. FOW [the 8th Coastal Defense Flotilla] in mid-September 2019. The reconaissance, identification and initial assessment of the object were done by underwater staff of the 41 Zespół Rozminowania Grupy Nurków Minerów 12. Dywizjonu Trałowców [sea-clearing divers' military unit].

As a result of the inspection and analysis of the collected material, the object detected in the water was classified as a D.P. 12.000 LB aerial bomb of British origin, commonly known as "Tallboy".

The neutralisation operation was commanded by Navy Capt. Piotr NOWAK and Navy Chorąży Michał Jodłoski from the Miner Divers Group from Świnoujście. Due to the nature of the object, the haste to remove it was inadvisable. The operation itself required large-scale preparations, a number of permits and the involvement of a number of both civil and military entities.

It took time for all the institutions participating in the action to develop the best option plan. An important factor defining the possibility of commencing the works was obtaining a certificate of the site cleanliness within a 200 m radius from the Tallboy, issued by the company executing the works commissioned by the Maritime Office. The site clearing procedure was completed at the end of August. As a result of searching the seabed, a large number of ferromagnetic contacts were found within a radius of several hundred metres from the Tallboy. Each of these several hundred objects was checked and removed by the 41. Zespół Rozminowania GNM or 37. Patrol Saperski [military demining unit] before the start of the operation, so that the Miner Divers of the 12. Dywizjon Trałowców [Minesweeper Squadron] could be assured that there was no other object containing explosives in the vicinity. Several hundred explosive and dangerous items, containing a total of over 3,000 kg of TNT, were removed from the Tallboy area.

While planning the operation, we considered several options. In conclusion, it was decided that the object would be neutralised in its location by means of the deflagration method. The underwater task specialists from 8. Flotylla Obronna Wybrzeża [the 8th Coastal Defense Flotilla] have been successfully using this method for several years to neutralise the remains of World War II. When planning the operation, we based on the experience gained from the neutralisation of smaller objects. Apart from the the 8. FOW diving groups, there is no subdivision that uses this method on such a large scale. Moreover, there have been no European nor world experience in neutralising Tallboy bombs so far. No one else had neutralised this type of bomb, in such good technical condition, located 12 metres under the surface of the water.

The object was so large that it required an unconventional approach and was a national, continental and even worldwide scale phenomenon. The Tallboy found near the Centrum ferry (Karsibór ferries) in Świnoujście was mostly buried in the sandy bottom. The bomb's technical condition was described as very good. The bomb was not fully unearthed due to its overall dimensions and the risk related to its movement, since long-term chemical processes of the explosive contained in the bomb could have detonated by impact, vibration or pressure variation even despite damaged detonators.

On the first day of the operation (October 12th), the army divers in cooperation with the civil company performed works including: reconnaissance of the object's location, levelling the bottom and partial exposure of the upper surface of the bomb body as well as the initial arrangement of the PVC ring in the axis of the bomb. They carried out the extraction of the content of the inside of the ring and the latter's gradual sinking into the bottom around the rear part of the bomb. The purpose of these activities was to prepare the bomb for deflagration. The works were continued on the next day. Favourable weather conditions in the following two days allowed to complete the major part of the operation sooner than originally assumed. The progress of the works was so advanced that a decision was made to deflagrate the object as early as on Tuesday afternoon.

During the main stage of the operation, deflagration was initiated remotely by radio. After a few seconds, the object detonated, which was one of the anticipated possibilities. The deflagration process turned smoothly into detonation and the part of the explosive that had not burned out exploded. As much as 37% of the explosive burnt during the first phase, which made the detonation much weaker than that of a full bomb.

All the assumed precautions took into account the possibility of the deflagration process turning into detonation. Firstlt, the method used did not bring any risk to soldiers and people directly involved in the operation. During the operation, there was no damage to hydrotechnical, navigation (glass facility, 100 m from the Tallboy), ferry, bridge, port, tunnel and gas infrastructure (gas pipeline 500 m away). People returned to their homes 60 minutes after the end of the operation, and shipping traffic on the Piastowski Canal was restored two hours after the end of the operation.

The Tallboy aerial bomb, the largest unexploded object in the history of Poland, a phenomenon on a global scale, has been made harmless and will no longer pose a threat on the Świnoujście-Szczecin fairway.

We would like to thank for the cooperation of all the entities participating in the operation. This huge operation involved, among others, the West Pomeranian Voivodeship Office, Świnoujście City Hall, the Maritime Office, the Police, the Border Guard, the Military Police, State and Volunteer Fire Brigades, the Municipal Police of Świnoujście and other municipal and voivode's services. We would also like to thank the representatives of the Poznań University of Technology for their cooperation.

We would also like to thank Sea Terra and DIVO companies for assigning the vessel and for their divers' assistance.

Tallboy was one of the largest bombs (second conventional) dropped during World War II. Its total weight amounted to nearly 5,400 kg, including 2,400 kg of TORPEX explosive with increased potency (which corresponds to almost 3,600 kg of TNT). Bombs of this type had a total length of 6.4 m, the length of the body without the tail was 3.15 m, and a diameter of 0.96 m. They were referred to as deep penetrating bombs. They were used to destroy strategic targets.

 

The preserved fragment of the Tallboy will be presented at the large-size exhibition "Relics of the Szczecin-Świnoujście Fairway".

 

The exhibition was created under the patronage and cooperation of the Ministry of Infrastructure of the Republic of Poland and thanks to the involvement and assistance of the following institutions and companies: the Maritime Office in Szczecin, the Szczecin and Świnoujście Seaports Authority, Zachodniopomorskie Stowarzyszenie Dziedzictwo Morza [the Western Pomeranian Association of Sea Heritage], Stowarzyszenia Miłośników Latarń Morskich [the Association of Lighthouse Lovers], the Museum of Polish Arms in Kołobrzeg, Polska Morska portal, the Maritime Cluster of Western Pomerania, the Inland Navigation Office in Szczecin and Wrocław and the consortium for the execution of the works on the DIVO fairway.

 

The Director of The Museum of Polish Arms in Kołobrzeg, Aleksander Ostasz, would like to thank in particular: Paweł Szumny, Jacek Kwiatkowski, Piotr Nowak, Michał Jodłoski, Arek Siewierski, "Woodhaven”, Andrzej Ditrich, Janusz Lemieszek and the staff of The Museum of Polish Arms, especially Marcin Bojanowski.