What are some useful parts you don't use enough?

[Fearless Son]

3 minutes ago, Aegolius13 said:

I've got to generally disagree with this one.  Monopropellant tanks have a worse dry mass fraction than LFO tanks, and the Puff has substantially worse ISP.  If I need to do more than dock, I'd rather just respect to reserve a little LFO and use a small engine or even a Vernor thruster.   

I've had a few cases (like escape pods) where a command pod's onboard monoprop storage met my delta-v needs, so I used that.  But in those cases the  Puff would be too big and heavy; the one-way thruster was a better fit.

The Puff might (might!) be a little more useful in low gravity landing situations, due to it's throttlability.  I sometimes use them for "land a new surface station on Minmus" contracts where I expect the trip to be on-way and I don't need a lot of delta-v.  A small monopropellant tank and a Puff or two usually gets a smallish module down pretty easily.

[Aegolius13]

15 minutes ago, Fearless Son said:

The Puff might (might!) be a little more useful in low gravity landing situations, due to it's throttlability.  

Not sure I follow how that differs from LFO engines, though.  Plus if you have an engine that's too powerful, you can use the thrust limiter slider (which stacks with the throttle) for extra-low thrust

Edited February 27, 2019 by Aegolius13

[Fearless Son]

17 minutes ago, Aegolius13 said:

Not sure I follow how that differs from LFO engines, though.  Plus if you have an engine that's too powerful, you can use the thrust limiter slider (which stacks with the throttle) for extra-low thrust

I meant it has a benefit over pure RCS thrusters due to having an adjustable throttle.  Makes for easier soft vacuum landings.

There is one benefit it has over LFO engines though, and that is that it doesn't require any fuel flow connection. Now, that's not much of a benefit, considering how the game currently handles fuel, but it can be handy if you don't want to fuss about which nozzle is draining from which tank.

[farmerben]

37 minutes ago, Fearless Son said:

 

There is one benefit it has over LFO engines though, and that is that it doesn't require any fuel flow connection. Now, that's not much of a benefit, considering how the game currently handles fuel, but it can be handy if you don't want to fuss about which nozzle is draining from which tank.

That and there is no exhaust occlusion.  Two small benefits. 

The puff is fully functional inside a cargo bay.  I think I can justify it for landing planes on Duna.  Possibly it could be justified for a sky crane to lift another vessel off the surface of Minimus... a sky crane that doesn't have to be shaped like an octopus.  For just an ordinary lander, I don't think if can be justified.

This is an interesting challenge.  Come up with a mission objective and a vessel that uses the puff engine to achieve it.  Post it to this forum and see if other players can perform better on just LFO engines.  By better I mean it cannot have more mass, or less dV.  

Edited February 27, 2019 by farmerben

[herbal space program]

3 hours ago, Capt. Hunt said:

don't they still despawn when your wheels touch down?

 

I never had any problems with that. They didn't disappear until I stopped completely.

[Aeroboi]

On 2/19/2019 at 8:00 AM, Aegolius13 said:

Fuel cells.  Personally I find it hard to overcome the stigma of using up a finite resource to generate electricity.  But a lot of the time they make for an easier / cheaper / more reliable setup compared to solar panels or RTGs.  The fuel cell arrays can also do some pretty good things when combined with ions.

I find that Fuel Cells can be very handy to operate ION engines in High atmospheric conditions like on a spaceplane.

I made this Duna ION spaceplane. It has enough Thrust and Delta-V to orbit and land 3 times over with spare fuel for navigation. It is also very good at skipping the atmosphere above 650 m/s and can travel to the other side 5 times over.
It uses only the Fuel cell array. Solar panels are to draggy for Duna spaceplanes and this way I could make a very streamlined ion orbiter that has similar drag co-efficient compared to a streamlined LFO spaceplane or typical fast jet.

It can also activate power generation for Kerbin SSTO's. If your Kerbin SSTO has ION engines to begin with it can already activate them high in the atmosphere (or use a lot of battery banks)
Since Kerbin SSTO's have LF/O to begin with a fuel cell array isn't that cumbersome. While a Ion/LFO hybrid doesn't have a lot of ION Dv it does pack mission room if your intention is to use your SSTO beyond Duna where solar panels are useless. Or use a lot of battery banks instead with a RTG which is usually more efficient for total Dv but on a SSTA with ISRU it can be particularly useful.

[farmerben]

Ion engines do not suffer exhaust occlusion.  They can be inside payload bays, in series with other engines, or have a docking port behind them.  

I haven't built hybrid ion/LFO vessels in a while, but they can be uniquely capable with great dV and TWR for difficult missions.  I sorta get bored if my ion only TWR is much below 20%.  But it is fun to make vessels that only need extra engines for special circumstances like landings.

[Aeroboi]

1 hour ago, farmerben said:

Ion engines do not suffer exhaust occlusion.  They can be inside payload bays, in series with other engines, or have a docking port behind them.  

I haven't built hybrid ion/LFO vessels in a while, but they can be uniquely capable with great dV and TWR for difficult missions.  I sorta get bored if my ion only TWR is much below 20%.  But it is fun to make vessels that only need extra engines for special circumstances like landings.

Mine has a TWR of 0.52 on Duna fully fueled Handles 10x physical timewarp using bettertimewarp mod.