Are submarine launches horizontal? is a general question and specifies by name two large ICBMs which are likely to need to be launched vertically.

Since the large naval submarines usually come ready-made with torpedo tubes, there are certainly rockets that launch from them that later break the surface and fly in the atmosphere, but the examples I've found are all weapons that target things on or near the surface of the Earth.

Question: Has a rocket launched from a torpedo tube ever reached space? It could be a test or one-time demonstration, it doesn't have to be a production design.

Examples of rockets launching horizontally from torpedo tubes:


Source: Harpoon click for larger

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    $\begingroup$ My feeling is that torpedo-tube-launched missiles are probably too small for any kind of launches to space and that submarine-based launch systems are probably descended from ballistic missiles, which have a lot more in common with orbital rockets (and are launched vertically). Apparently a few such systems exist. $\endgroup$
    – kwc
    Jan 18, 2021 at 7:08
  • $\begingroup$ As a rule-of-thumb check, a modern Mk 48 torpedo weighs just shy of 1700 kg and is 5.8m long x 0.53m in diameter. I'm having trouble finding sounding rockets / rocketsondes that are that small, though maybe one exists. $\endgroup$
    – Erin Anne
    Jan 18, 2021 at 8:59
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    $\begingroup$ mind that Regulus was not launched from a torpedo tube, but from a launch ramp on the rear deck of the submarine, in similar fashion to how Germany launched their V1 cruise missiles. $\endgroup$
    – jwenting
    Jan 18, 2021 at 12:55
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    $\begingroup$ @uhoh I'm excited that the "smallest sounding rocket" one indicates that space-capable rockets have come in sizes that would fit in a torpedo tube. Orbit seems out of reach without much larger tubes though. Neat $\endgroup$
    – Erin Anne
    Jan 18, 2021 at 23:17
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    $\begingroup$ If an SLBM missile tube can be considered a 'torpedo tube', then yes. A Trident II SLBM is a three stage rocket that flies well into space (as high as 1200 km), and can travel 12,000 km at a speed of over 25,000 km/h. It has a star tracker for space navigation, and a hypersonic re-entry. It is launched from underwater like torpedos, but vertically from vertical launch tubes. Compressed air blows the missile out of the sub before the rocket ignites. I didn't post this as an answer because I wasn't sure if it counts. $\endgroup$
    – Dan Hanson
    Jun 14, 2022 at 1:42

2 Answers 2


Certainly not to Orbit

The smallest rocket to deliver a payload to orbit is a Japanese sounding rocket that is 9.7 meters tall.

The US heavy-weight torpedo (Mk. 48 ADCAP) is 5.8m and the Russia heavy-weight torpedo (Type 65) is 9.1m long. All three of these objects are roughly the same diameter (0.5-0.6m).

Torpedo tubes are basically the same size as the torpedoes that go in them. So the smallest rocket to reach orbit would not fit in standard torpedo tubes in either the US or Russian Navy.

Karman Line is Feasible

The S-210 Japanese sounding rocket would physically fit in the both torpedo tubes, and can pass the Karman line, so it is feasible that a horizontally launched rocket / missile could reach 100km.


The Exocet SM39 is an old version introduced 1985 for submarines. It used a solid rocket engine, the maximum distance was only 50 km. Wingspan was 1.09 m.

The newest version MM.40 Block 3 was introduced 2008, it uses a booster for the start and a TRI-40/263-Turbojet. Maximum distance was 200 km, wingspan 1.13 m. Speed of both versions was about mach 0.9.

The Harpoon was introduced 1977, it uses a Teledyne CAE J402 turbojet and a solid propellant booster for launch. Maximum distance 280 km, speed mach 0.7, Wingspan 3 ft (0.91 m).

So all these examples of cruise missiles that can come out of torpedo tubes are designed for horizontal short distance sub sonic flight using wings. Two of them are equipped with air breathing turbojets. Mass less than 1000 kg, diameter less than 400 mm, length less than 5 m. Is there any example of an orbital rocket being so small and single stage?

Shtil' is 14.8 meters tall and 1.9 meters in diameter. It weighs about 39.3 tonnes (metric tons) at liftoff, three stages. It can come out of submarine launch tubes.

So a torpedo tube seems to be much too small for an orbital rocket with a small payload.

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    $\begingroup$ -1 because this is currently not an answer to the question asked. Those things are simply examples showing that rockets can come out of torpedo tubes. Saying that they didn't go to space is not helpful because there is no presumption that they could have. $\endgroup$
    – uhoh
    Jan 18, 2021 at 18:01

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