The construction used a German tender locomotive of class 57 (it is not certain whether the same locomotive was in the train's consist throughout its entire lifetime - any similar locomotive could have been used) and two double-axle cars belonging to the Reichsbahn - a flatbed one (on the latter they placed a non-running tank BT-5 without tracks and armament - the gun was replaced by a heavy machine gun vz. 24) and covered. The locomotive itself was not armoured, unlike the wagons. The covered wagon was equipped with two single-seat machine gun turrets on the roof, probably from a T-28 tank, or T-35 armed with a light machine gun vz. 26 located at both ends of the wagon. In addition to the turrets, there were two gun turrets on each side of the wagon where 2 light and 2 heavy (one on each side) machine guns of 7.92 mm caliber were placed. The wagons were plastered with armour plates from broken Soviet tanks.
The set was supplemented at both ends by so-called buffer wagons (1 to 2) filled with sand and used to activate mines. Later, one more armoured carriage (probably built on a flatcar chassis) was added to the set, as the train's original armament proved insufficient in combat. This wagon had an armoured superstructure in the middle (shelter for the gun crew), on the roof of which was again a machine gun turret from a decommissioned Soviet tank armed with a machine gun vz. 26 and on the platforms at both ends of the superstructure were placed heavy weapons - an 81 mm mortar vz. 36 and a 37 mm anti-tank cannon KPÚV vz. 37.
The crew consisted of 1 officer, 23 men + 2 sappers to defuse mines on the line.
Slovak soldiers used the train for more than a year. The train patrolled the line daily, delivering mail, provisions or taking part in anti-partisan fighting. The train did not always operate as a compact unit - many times individual cars were deployed separately to protect other units. The train's combat career ended on 27.05.1943, when at about 10:30 a.m. it ran into a mine while moving from Ovruč to Jelsko (about 21 km south of Jelsko, 3 km north of the settlement of Slavečna). The mine destroyed a locomotive, an armoured carriage and a trailer. The explosion wounded one soldier severely and one slightly. After this date there are no reports on the activities of IPV Orol.
For more detailed information on the combat actions of IPV Eagle, see the freely available source (VHÚ/Archive) listed below.
Vojenská história 4/2008, article by Pavel Michianik "Improvised armoured train of the Zaisťovacej divízie Orol", VHÚ, Bratislava 2008, ISSN 1335-3314
http://www.vhu.sk/uvodna-stranka/
Merging the contributions of Košićan and perun39 for compactness of the topic.
Edit: brano.