How come "Thuds" aren't used often? (Looking at Other's Videos and pics)

[Kerbart]

Skipper + Thuds = Great when you don't have a Mainsail yet in Career. But what's the point of having an engine that's only attractive during a very small time frame in Career? Well, because it's bloody handy when it's there and you need it. Case in point: the Flea.

[cantab]

The Thud isn't a great engine, having low TWR and low Isp. It's a convenient form factor, but the VAB is flexible enough for other engines to work well.

Sometimes use cases do turn up. I used Thuds for the first stages on some of my Serran landers. One Swivel would have made the already-tall landers even taller and two Swivels would have been massive overkill, but a pair of Thuds were just right. (Serran's an atmo body in the New Horizons planet mod, so Poodles and Terriers were out).

[KerbonautInTraining]

Atmospheric lander descent stage.

I rest my case.

Looking through this thread I realized my 6 kerbal 2.5m duna lander would have been much easier to land if I had used 2 thuds instead of 4 radially mounted terriers, and would eliminate the need for me to use the 2 ascent terriers to land.

They would also be useful on Laythe for this purpose. However, this is all under the assumption you have a dedicated descent stage.

[Gojira1000]

I tend to use them on 50-ton-plus oddly-shaped science or colony stations for landing them wherever. And that's about it, really.

[WhiteKnuckle]

51 minutes ago, KerbonautInTraining said:

Atmospheric lander descent stage.

I rest my case.

 

Um no.

Aerospikes are your friend anywhere with an atmosphere. The only advantage the thud has is gimbaling.

[Waxing_Kibbous]

I've used Thuds on regular landers (not too much because of ISP), a bit more on module delivery units, not on Minmus where they are overkill, but on the Mun. They are good for a one way disposable space elevator.

[sal_vager]

I like dual thuds as an upgrade from the Swivel as a lift engine, for just 0.4 more mass you have more power, better ISP at launch and the huge gimbal for stability.

[Nothalogh]

I use Thuds all the time on my low tech 1.25m boosters as a first stage engine.

The gimbal is a godsend it the early stages of career.

Also, a little bit of monkeying around, and you can make an Atlas-ish 1.5 stage with them

[KerbonautInTraining]

7 hours ago, WhiteKnuckle said:

Um no.

Aerospikes are your friend anywhere with an atmosphere. The only advantage the thud has is gimbaling.

The Thud is designed to be radially mounted and is much smaller

In other words: Muh aesthetic 

Edited January 28, 2016 by KerbonautInTraining

[WhiteKnuckle]

15 minutes ago, KerbonautInTraining said:

The Thud is designed to be radially mounted and is much smaller

How "much smaller" do you want to get? The Aerospike is a short 1.25m engine and only .1t heavier than the Thud.

 

Is it "much smaller" once you factor in all the extra fuel you have to carry to get the same dv?

 

As a booster it's fine, the low ISP isn't important, but no one should confuse it for a final stage or lander engine (unless you have more fuel than you know what to do with)

[FancyMouse]

I'm actually curious if the model change in 1.0.5 reduces its drag?

[Temstar]

1 hour ago, KerbonautInTraining said:

The Thud is designed to be radially mounted and is much smaller

Aerospike is surface attachable which is infinitely more flexible.

[MrOsterman]

7 hours ago, Temstar said:

Aerospike is surface attachable which is infinitely more flexible.

And Ugly.

I'm embarrassed to look at the bottom of my latest Duna lander.

[KerbonautInTraining]

9 hours ago, WhiteKnuckle said:

Is it "much smaller" once you factor in all the extra fuel you have to carry to get the same dv?

 

As a booster it's fine, the low ISP isn't important, but no one should confuse it for a final stage or lander engine (unless you have more fuel than you know what to do with)

A dedicated atmospheric descent stage only needs some 500m/s of delta V. The difference in isp won't really matter. 

Don't get me wrong, I'm not trying to say "you should use this engine" I'm saying "this engine is well suited for some applications under certain circumstances in my opinion"

[radonek]

On 26. ledna 2016 at 7:49 AM, KSK said:

Stability. Four tanks with a landing leg on each gives you a nice wide base for your lander, making it easier to land on slopes. That was always my reason anyway. 

Exactly. Then you add those radial tanks onto decouplers and set up asparagus to squeeze a bit of spare delta-v, and find out its handy to have engine on each tank to have fuel readout for that stage.

That said, I would like to use Thud to set up Atlas-style booster-sustainer design, but it would need integrated decouplers and fuel drain for that. Thud+decoupler+fuel line is too much parts and drag.

[KSK]

On 26/01/2016 at 5:09 PM, Vegetal said:

You guys are missing a point: It has huge gimbal range. It's like a tiny Vector, just not OP. I use it for small shuttle-like spacecraft, it's well suited to them.

I don't use it for anything else though, it's terrible in vacuum. Using it as a lander engine is a waste.

This is not my idea by any means - can't remember where I got it from I'm afraid so can't attribute. Anyhow - the Thud makes (or used to make) a spiffy rocket assist for very early recon planes. The early jet engines are rather altitude limited and sometimes you get a contract to take readings from above that altitude. What to do?

Solution - go Kerbal and add rockets to everything! Build your normal early-game jet and strap a pair of Thuds to the back. Climb as high as you can on jets, zoom climb to altitude using the Thuds, grab yer science and hope you can glide back to somewhere suitably flat for a deadstick landing.

[juanml82]

 I made some shuttle like ore drilling/refining rovers with the MK3 parts and the big rover wheels. Since I need to land them "on the belly" instead of "on the tail" and they aren't exactly symmetrical, the gimballing range of the thuds and their low size compared to a vector+fuel tanks makes them a good choice to maintain control