More powerful Mite & Shrimp

[T1mo98]

So with the new update came a large number of new SRB's.

They all look amazing and are very useful.

Except the Shrimp and Mite in my opinion.
The problem with these two is how little thrust they have. The Mite having less than even a Sepratron.

The only use-case I can see for them is as an upper stage kickstage, when instead I think they could also be really useful as a booster or for a custom Launch Escape System (especially the Mite).
 

I think if the thrust of the Mite is upped to somewhere around 70 or 80 kN and the Shrimp to around 100-110 kN, they could be a lot more useful. They could still be used just fine as a small kickstage by reducing thrust.

Also, it would make the massive exhaust plume a lot more logical.

[Pds314]

The Shrimp has 30 kN in a 0.625m engine. That's above state of the art. Not below. And where do you need such a minuscule diameter engine applying that much force? A 4-meter-long tube that needs to be offset to one sides beyond impractical as a LES.

 

As to the mite, well, it weighs 375 kg fully fueled and 75 kg empty. It's lighter than a twitch or a spark and has an integrated tank of fuel.

And if you want custom LES, separatrons are a lot better for, well, separating things.

 

Also... the Shrimp and Mite are not underpowered for SRBs... their efficiency specs run circles around every other SRB smaller than Kickback. Giving the Shrimp 100 kN would give the booster, fuel tank included, an empty TWR of 67. Which would be better than just about everything besides separstrons. Giving the Mite 75 kN would give it an empty TWR of 100, which is bonkers.

Edited October 19, 2019 by Pds314

[Pds314]

Comparison of Mite and Shrimp to other SRBs and two LFBs. It isn't them that need a buff. Or at most it should be maybe a buff for the mite to 20 kN and Shrimp to 40 or something. Not 80 and 110. Unless we're also gonna give the spark and twitch buffs to 90 and 65 or something, and then that would kick off a chain reaction in other buffs of LF engines.

SRB Performance specifications (With LFB included for comparison)

Name	Empty mass	Total mass	ISP(vac)	ISP(SL)	Thrust (vac)	Thrust (SL)	Mass ratio	Delta-V (vac)	Delta-V (ASL)	TWR(full, vac)	TWR(full, SL)	TWR(empty, vac)	TWR(empty, SL)	Total impulse (vac)	Total impulse (SL)	IWR (Vac)	IWR (SL)
Separatron	12.5	72.5	154	115	18.0	13.4	5.80	2655	1982	25.3	18.9	146.8	109.7	91	68	1.25	0.93
Mite	75	375	210	185	12.5	11.0	5.00	3314	2920	3.4	3.0	17.0	15.0	618	544	1.65	1.45
Shrimp	150	825	215	190	30.0	26.5	5.50	3594	3176	3.7	3.3	20.4	18.0	1423	1258	1.73	1.52
Flea	450	1500	165	140	192.0	162.9	3.33	1948	1653	13.1	11.1	43.5	36.9	1699	1442	1.13	0.96
Hammer	750	3562.5	195	170	227.0	197.9	4.75	2980	2598	6.5	5.7	30.9	26.9	5378	4689	1.51	1.32
Thumper	1500	7650	210	175	300.0	250.0	5.10	3355	2796	4.0	3.3	20.4	17.0	12665	10554	1.66	1.38
Kickback	4500	24000	220	195	670.0	593.9	5.33	3612	3201	2.8	2.5	15.2	13.5	42070	37290	1.75	1.55
Pollux	8000	51500	225	200	1300.0	1155.6	6.44	4109	3652	2.6	2.3	16.6	14.7	95982	85317	1.86	1.66
Thoroughbred	10000	70000	230	205	1700.0	1515.2	7.00	4389	3912	2.5	2.2	17.3	15.5	135331	120621	1.93	1.72
Clydesdale	21000	144000	235	210	3300.0	2948.9	6.86	4437	3965	2.3	2.1	16.0	14.3	283460	253304	1.97	1.76
Twin Boar	10500	42500	300	280	2000.0	1866.7	4.05	4113	3839	4.8	4.5	19.4	18.1	94143	87867	2.22	2.07
TB + Orange	14500	78500	300	280	2000	1866.7	5.41	4969	4638	2.6	2.4	14.1	13.1	188287	175734	2.40	2.24

 

Edited October 19, 2019 by Pds314

[T1mo98]

15 hours ago, Pds314 said:

The Shrimp has 30 kN in a 0.625m engine. That's above state of the art. Not below. And where do you need such a minuscule diameter engine applying that much force? A 4-meter-long tube that needs to be offset to one sides beyond impractical as a LES.

 

As to the mite, well, it weighs 375 kg fully fueled and 75 kg empty. It's lighter than a twitch or a spark and has an integrated tank of fuel.

And if you want custom LES, separatrons are a lot better for, well, separating things.

 

Also... the Shrimp and Mite are not underpowered for SRBs... their efficiency specs run circles around every other SRB smaller than Kickback. Giving the Shrimp 100 kN would give the booster, fuel tank included, an empty TWR of 67. Which would be better than just about everything besides separstrons. Giving the Mite 75 kN would give it an empty TWR of 100, which is bonkers.

2 things.

1. I currently use sepatrons. I need more than 50. I'd rather that be replaced, either with a couple small SRB's (like a more powerful Mite) or a Thud without the exterior.

2. I'm not saying the thrust should be increased with every other spec staying the same. Here's a fun idea, have variants. A powerful, less efficient and heavier version and one like we have now.

 

I simply want them to be more useful than as a vacuum booster or on really small launchers  Because they're pretty useless on larger launchers. They hardly save any DeltaV or increase payload capacity.

[Tweeker]

While I could stand a more powerful Mite,  it's thrust is about inline with with many kick motors. It's ISP could be raise to emphasis it's role, the  zefiro upper stage on the Vega for example has an ISP of 295, and the altair has an ISP of 289. 

The shrimp however could stand to have alot more thrust, the castor motors have 745 KN of thrust,  {@ 1 meter diameter } As a rule of thumb I find motors should scale to 20% of real world thrust in KSP, so ~150 Kn 

[PositronLance001]

I tested them and they're totally ok. no buff needed.