Evaluation of the Plant from a Military Perspective.
	I evaluate the plant as a developmental step, which in present form, U-180 does not yet represent a usable weapon.
	The following speaks against the plant.
	1.)  The engines must be removed after each long-distance patrol because they cannot be overhauled in the boat, meaning long shipyard periods, opening up the pressure hull each time.
	2.)  The plant requires considerably numerous pressure hull pass through and therefore brings numerous sources of danger, including operator errors which are also possible to an increased extent.
	3.)  Of the 6 exhaust gas valves 2-3 leaked moderately during the entire patrol despite grinding every 4 hours.  In some cases, the boat took on to 4 tons of water in 1-2 hours.  Re-grinding submerged brought some improvement, but can only be done at a shallow depth and is not possible in every situation. The functioning of the exhaust valves was unpredictable.
	4.)  In this boat the stern tubes were made smaller for reasons of space and they have always leaked for a short time after repacking.  The boat took on an average of 3 cbm of water per hour as a result of paragraphs 3 and 4, that means of course it is necessary to pump 3 cbm water [from the regulating tank] and 900 liters from the trim tank submerged.  Water monitoring must be practically constant and the pumping means must be in operation in order not to have the regulating tank and rear trim tank empty in a short time.  Similarly, the amount of water in the boat has a very large influence on the depth control characteristics, because the diesel bilge is very low, the water soon rises over the floor plates and can then move freely in the 17-meter-long room.
	5.)  The entire system is too cramped, too confusing and above all too inaccessible especially in regard to the very extensive tangle of cables.  Finding leaks often takes days, even though elimination would be possible in the shortest possible time.  The approach to a malfunction usually requires extensive and lengthy preparations.
	6.)  At high speed settings the engines are significantly louder that the other type and are easily heard on the surface.
	7.)  In my opinion, fresh water cooling of the engines is a significant complication for U-boat use.  U-180 has a total of 14 coolers, while the IX D II boat gets by with 2.  Fresh water can easily become a vital issue on this type.  The fresh water maker failed right at the start of this patrol. The numerous fresh water leaks of the diesels, fresh water consumption of the crew and the battery could not be met by one freshwater maker, so water continually had to be taken from the tanks and after 5 months despite thrifty consumption with an initial inventory of 9 cbm fresh water the boat returned to port with 500 liters.  The fresh water consumption of the diesels continually increased despite soldering of all detected leaks.  During the entire journey, the crew only received one glass of fresh water per day for teeth cleaning, in terms of health skin damage was observed as a result of the exclusive use of seawater.

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	8.)  The engine consumption at transit speed was around 30% more fuel than Type IX D 2; the boat has a correspondingly lower action radius.
	9.)  The engines smoke at the transition from transit speed - 7 to 8 knots - at higher speed settings so strongly that an unseen operation is practically out of the question, the smoke lasts a minimum of 1/2 to one hour until the exhaust gas paths are clean.  Continuous warming of the engines - switching the engines every 2 or 4 hours - brought no improvement.  The only possible remedy was to increase the cruising speed to 10 to 12 knots (higher exhaust gas temperature, better combustion). However, with the inevitable strong reduction of the range of action at high speeds, the normal plume of smoke is substantial and not bearable in good visibility.
	10.)  The plant requires very good and conscientious personnel with thorough special training.  The technical manpower is about one Petty Officer and 2 Men larger than with Type IX D 2, whereby as compensation the E-motor section on U-180 is reduced but also inadequately manned.
	11.)  Bringing new crew-members aboard (technical) requires longer time than in other Types to get up to the same level of training.
	12.)  Due to its subdivision, the plant is not as quick to get to AK as in other boats.  Likewise, the overall system is very susceptible to faults, especially in relation to the cable tangle-pipe breaks.  Cooling water jacket, oil jacket, air in piping and leaks so that when you go up to high speed settings failures must always be expected, which force at least a temporarily shutdown of engines; prolonged extension of higher speed is therefore a matter of luck.  Against this fact, the best staff and conscientious operation is powerless.  It lies in the sensitivity of the plant.
	13.)  Since the engagement of the shaft on the transmission requires a certain amount of skill, the time required for this is different and the boat is therefore not ready to immediately start the diesel. It is therefore recommended to do the coupling before surfacing while submerged.
	14.)  The engines themselves have proved themselves in continuous operation, although rarely all five engines were fully operational at the same time. (Reason all the accessories). Turns for U.A.K. were never been reached during the patrol.
	15.)  It should be remembered that the plant was never pushed during the entire patrol, but was driven very carefully and gently at transit settings.  Only two times die we go to AK for the purpose of exercise for a very short time at AK. (Fuel situation).  In both cases full RPM were not reached and in both cases the engines had to be shut down for malfunctions.
	16.)  The trim condition of the boat was not acceptable: in order to obtain sufficient filling for the rear trim tank for a good part of the return, in the bow room it was necessary to have 7 torpedoes 2 tons of metal, trim weights, torpedo compensating tanks full, both forward upper decking torpedo canisters flooded.  In the stern room only 2 torpedoes, torpedo compensating tanks empty, no trim weights.  The majority of the listed points do not pose any basic concerns for the

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	plant, as they can be corrected or improved for example already the strong transmission oil losses and the air in cooling water after each blow out were eliminated temporarily by minor changes.
	It remains to be seen whether the total expense with its unlike other types but still existing considerable complications, larger fuel consumption and possibly correctable deficiencies are in practice worth the only slightly higher speed of this type.  The most serious point at the moment for which the plant seems unusable at the front is the tremendous smoke is the Diesel, which takes one of the boat's main weapons - invisibility - and just in the moment of enemy sighting, where normally speeding up is considered.  The boat had only two options, either to be seen (smoking, increased speed) and thus to give up the best chance for attack or to dive immediately on sighting the enemy and try to approach submerged, which in most cases, depending on the situation when sighting a matter of pure luck.
	Korv. Kpt. and Kommandant