Advantages of light 'Mechs

[Matti]

Let's talk about advantages of light 'Mechs against heavier ones. Why would you, or anyone, take Panther over Griffin, or Valkyrie over Dervish? Why did Captain Mercer Ravannion take Stingers and Wasps instead of Jenners and Phoenix Hawks? Why haven't more factories been converted to produce stronger units, like one originally producing Sentinel was converted to produce Hatchetman?

Costs
Obviously lighter 'Mechs are cheaper to produce, sell, and buy. Also likely faster to produce with equal amount of resources, and easier for maintenance. These factors lead to better availability, and most certainly there are at least some situations where full company of Stingers is more useful than one lance of Phoenix Hawks.

Weight
This could be more significant than first meets the eye. Heavy factor in transportation: there are limits on how much VTOL can lift up. Aforementioned Captain Mercer Ravannion may have crammed most of his 'Mech force into Mule-class DropShip as cargo: 20-tons per 'Mech. This way more 'Mechs can be transported with less 'Ships.

Other factors
Time and technical resources. It took several years to convert a factory from Sentinel to Hatchetman production. In that time that factory (or part of the factory?) didn't build any 'Mechs. There is a historical example in time of Second World War, in USA: M3 tank remained in production throughout the war, likely because somebody decided more M3 right now is better than more M4 next month (or later). On top of a 'Mech factory itself, fusion engine factories and other industries would need conversions too. Much easier said than done.

Is there anything else to add? Fire at will.

[McSlayer]

you would only take it if you were scouting and needed something faster, or if you were in a FPS game and wanted something OP that was beefed up to make it worth taking.

[Kovax]

There's a reason why real navies in the 20th Century built more Destroyers than Battleships.  The Battleship can only be in one place at a time, and you can afford to produce a lot more DDs than BBs, send them to remote places faster, and with less fuel expense.  The only times you needed the BBs were when confronting another BB or for heavy shore bombardment.

Mercer Ravannion apparently had the Stingers and Wasps available in quantity, while Jenners and Phoenix Hawks would have been in much shorter supply.  Besides, we gamed out a situation along those lines using equal tonnage (before BV was a thing), and the Blackjacks had to be given a few breaks to make it playable, such as having the opposition come on in waves, one lance at a time 3-4 turns apart.  Even then, we had to force the players running the Lights to engage with only similar or marginally higher numerical superiority, rather than sit back until the next wave came on, otherwise the Lights still took losses, but barely more than the Mediums.  Swarming a single target works, especially when you can put your swarming units practically anywhere you want them to be.

In 3025 with Regular pilots, many of typical Lights can rack up high enough movement modifiers to make a fight difficult for slower units.  That doesn't apply to 'Mechs like the Panther or Valkyrie, which have no such advantages over heavier designs.  The Panther, in particular, is at a speed AND tonnage disadvantage against Mediums like the Griffin or Dervish, although I'd probably prefer fielding a Locust for engaging a Panther, and expect to either come back with a kill and practically no damage at all, or not come back.

Once better gunnery skills or Pulse weapons come into play, those Lights are simply targets, and "Speed=Armor" is no longer sufficient to keep the thin-skinned units alive.

[Daryk]

The one thing Ravannion overlooked was that people are expensive.  Not as expensive as ALL 'mechs, but expensive nonetheless.

[MoneyLovinOgre4Hire]

Sometimes there are situations where you just don't want to show up with heavy mechs.

[massey]

Sometimes you only need a light mech.  A lance of bugs, 2 Stingers and 2 Wasps, is death on 8 legs to small vehicles and platoons of infantry.

[R.Tempest]

 It may be Succession War era economics. It's probably faster/cheaper to rebuild a light mech factory than one that produces heavier models. Also, the heavier factory's are more attractive as a strategic target than the light ones (how many 'Battles for Hesperus' did we see?).
 Some jobs are performed better by lights. A lance of Stingers will be far more effective at crowd control/riot suppression/counter-insurgency than a single Zeus or pair of Blackjack's, although this is more of a strategic effect. In a one off game this doesn't really show very well.

[SCC]

There are problems with what you're talking about. First of all Light 'Mechs also die a lot easier. Secondly you're assuming that the cost of 'Mechs is linear with size/weight and combat power, we don't know this, it may well be that there's a base cost y, a tonnage scaling cost x, and a speed scaling cost z. Also given how readily armor and other repair materials are it's probably A) easier to repair a damaged heavy or assault after it's tangled with a lance of lights', B) There's probably some core component like the reactor, or more likely something in the control system that's limiting 'Mech supply. Also C) the owner of that heavy that tangled with your lights' can now but your lights' into his service, hopefully better then you. Thirdly the kind of hit and run tactics that could make lights' usable require more highly trained and experienced pilots, which aren't going to be easy to come by. In conjunction with my third point, the kind of extreme mobility present in BT would likely actually render hit and run tactics unworkable.

There's a reason why real navies in the 20th Century built more Destroyers than Battleships.  The Battleship can only be in one place at a time, and you can afford to produce a lot more DDs than BBs, send them to remote places faster, and with less fuel expense.  The only times you needed the BBs were when confronting another BB or for heavy shore bombardment.
-snip-

Two problem with this: 1) You're assuming that light 'Mechs are analogous to Destroyers in power, and that it very likely mistaken. 2) Destroyers worked because their primary purposes was to carry torpedoes, a great equalizer, something that doesn't exist in BT.

Sometimes you only need a light mech.  A lance of bugs, 2 Stingers and 2 Wasps, is death on 8 legs to small vehicles and platoons of infantry.

But pretty much only that.

[Col Toda]

They are fine before pulse lasers, targeting computers and precision ac ammo . After that you are better off using combat vehicles for the light mech roles . A light mech still eats a 150 ton mech bay . That is 3 50 light vehicle bay . Most of which are better armored than a light mech  .  A faux light mech like a Cicada  at least has more internal and about the same armor as a light  mech as fast and well about as well  armed . So I do not use light mechs much after  3058 and not at all by 3072 when the infrastructure for combat vehicles with fuel cell engines are just about everywhere in the Inner Sphere. As for cost the XL . engines on the later light mechs make them very expensive and more vulnerable.  Cheap disposable and replaceable combat vehicle attrition units are the way to go .

For Solaris VII I made a 22 million C bill  light mech that was great but Solaris VII runs on a different  business model than a mercenary combat unit .

[Kovax]

There are problems with what you're talking about. First of all Light 'Mechs also die a lot easier. Secondly you're assuming that the cost of 'Mechs is linear with size/weight and combat power, we don't know this, it may well be that there's a base cost y, a tonnage scaling cost x, and a speed scaling cost z. Also given how readily armor and other repair materials are it's probably A) easier to repair a damaged heavy or assault after it's tangled with a lance of lights',...

We have rules detailing the costs and repair modifiers, and there are actually a couple of exponential effects to cost, although most of the costs are indeed linear.  A faster 'Mech pays more for its engine, and possibly gyro, than a slower 'Mech of comparable tonnage, but speed increases for heavier units require massive and prohibitively expensive engines and correspondingly larger and more expensive gyros.  A Locust pays a far lower base cost for its 160 rated engine than an Atlas does for its 300 rated engine, and that cost rises exponentially with engine size, not linearly.  There's also a final cost modifier based on tonnage, so even after the larger engine, bigger gyro, and other factors are taken into consideration, you still have a higher cost modifier for the sum of those components merely because they're for a larger 'Mech.  The 20 ton Wasp or Stinger would pay a +20% final cost modifier added to the sum of the individual components upon final assembly due to tonnage, but an Atlas would pay a +100% cost increase for EVERY component due to its 100 ton frame.

Armor repairs cost the same for the same amount of damage, regardless of tonnage.  Replacement actuators and other internal components do cost more for the larger 'Mech, although weapons don't.

Simply look at the prices.  That fast Locust is just over 1.5 Million C-Bills (a huge chunk of that is engine and gyro cost), and a Stinger or Wasp is even cheaper, while an Atlas is in the 8 Million range.  You can field a lot of "bug 'Mechs" for the price of an Atlas, even assuming that the factory for the Atlas hasn't already been destroyed as a high priority target.

[Getz]

There's a reason why real navies in the 20th Century built more Destroyers than Battleships.  The Battleship can only be in one place at a time, and you can afford to produce a lot more DDs than BBs, send them to remote places faster, and with less fuel expense.  The only times you needed the BBs were when confronting another BB or for heavy shore bombardment.

A large part of why navies built so many Destroyers in was because they lost so many.  In WWII naval terms vessels like Destroyers were expendable by design - their purpose was to screen less expendable assets whether that was a convoy or a squadron of Battleships.

You can use light mechs in the same capacity if you want to - in fact some lights like the Commando and Battle Hawk seem to be purpose designed for the role.  I would much rather lose a Commando driving off a P-Hawk than give that P-Hawk an unmolested run at the rear armour of my Zeus', for example.

[Minemech]

You can use light mechs in the same capacity if you want to - in fact some lights like the Commando and Battle Hawk seem to be purpose designed for the role.  I would much rather lose a Commando driving off a P-Hawk than give that P-Hawk an unmolested run at the rear armour of my Zeus', for example.

While it might screen off Locusts, and Spiders, I would advise against trying to use them to keep P-Hawks away. For one thing, it means that that mech might be within firing range of the Shadow Hawks, and Griffins. For another, P-Hawks can handle them in short order.

[Simon Landmine]

Another consideration is when playing on a strategic level (or on _really big_ maps on MM) ... if you've got no functional satellite overwatch, you may need a decent number of fast recon units to fan out and find the enemy - and then run away from them when located.

[Matti]

Sometimes there are situations where you just don't want to show up with heavy mechs.

This argument could be used for 'Mechs in general: why use any 'Mech for recon at all when Savannah Master and Ferret are around?

[Retry]

This argument could be used for 'Mechs in general: why use any 'Mech for recon at all when Savannah Master and Ferret are around?

The latter is in mortal danger to unexpected MANPAD popups or the weakest of AA.  The former's reconnoitering can be foiled by a waist-high treeline.

[Cannonshop]

Let's talk about advantages of light 'Mechs against heavier ones. Why would you, or anyone, take Panther over Griffin, or Valkyrie over Dervish? Why did Captain Mercer Ravannion take Stingers and Wasps instead of Jenners and Phoenix Hawks? Why haven't more factories been converted to produce stronger units, like one originally producing Sentinel was converted to produce Hatchetman?

Costs
Obviously lighter 'Mechs are cheaper to produce, sell, and buy. Also likely faster to produce with equal amount of resources, and easier for maintenance. These factors lead to better availability, and most certainly there are at least some situations where full company of Stingers is more useful than one lance of Phoenix Hawks.

Weight
This could be more significant than first meets the eye. Heavy factor in transportation: there are limits on how much VTOL can lift up. Aforementioned Captain Mercer Ravannion may have crammed most of his 'Mech force into Mule-class DropShip as cargo: 20-tons per 'Mech. This way more 'Mechs can be transported with less 'Ships.

Other factors
Time and technical resources. It took several years to convert a factory from Sentinel to Hatchetman production. In that time that factory (or part of the factory?) didn't build any 'Mechs. There is a historical example in time of Second World War, in USA: M3 tank remained in production throughout the war, likely because somebody decided more M3 right now is better than more M4 next month (or later). On top of a 'Mech factory itself, fusion engine factories and other industries would need conversions too. Much easier said than done.

Is there anything else to add? Fire at will.

with units like the Panther, the main driver is cost.  The PNT-9R is cheaper for House Kurita to build, than a better mech is to import.  (Kind of also why the Valkyrie kept being made after 3025).

In some cases, Weight can be a significant factor.  like...bridges, or other structures.  a Light 'mech might be able to actually land on a roof (and walk around) that a mech only 5 tons heavier will fall right through.  (or, as happened in canon, a light 'mech running on lava-tubes might lure a heavier or heavy to their doom by crossing one full of hot, sticky, molten rock.)

certain quirks become relevant as well-like size, low profile etc.

[Matti]

certain quirks become relevant as well-like size, low profile etc.

I don't recall Total Warfare or Tactical Operations detailing such things...

[Cannonshop]

I don't recall Total Warfare or Tactical Operations detailing such things...

considering that I don't use 'Quirks' anymore than employing 'powerups'...but it was included in some of the optional-optional rules, so meh.

[Natasha Kerensky]

Within a given speed band (4/6, 5/8, 6/9), you’re usually better off with a heavier mech.  But there are exceptions:

— Really heavy engines.  A 50-tonner going 8/12 is usually less efficient than a lighter design going 8/12 due to its 400-rated engine, for example.

— Breakpoints on Jump Jets, Gyros, and other weight-sensitive components.  A 50-ton jumper is usually better than a 60-ton jumper, for example.

— BV, Tonnage, and Cost Caps.  Lighter mechs are generally going to use up less of your budget under any of these metrics.  You can only afford what you can afford.

— Quirks.  Only light and medium mechs can have the Compact quirk, which is useful logistically.  Fluff-wise, they also lend themselves to the Narrow/Low Profile quick, which give a to-hit bonus.  (But in theory an assault mech could have this quirk.)

Part of the problem with lighter mechs as technology gets deadlier is that they’re not expendable enough.  Something less expensive that can be fielded in larger numbers would often be more useful.  And the Clans went that way with the ProtoMech.

[Weirdo]

The latter is in mortal danger to unexpected MANPAD popups or the weakest of AA.  The former's reconnoitering can be foiled by a waist-high treeline.

This, very much. No matter how cheap a conventional vehicle is, no vee can ever match a mech's ability to traverse almost any terrain in almost any weather, and those that can are either extremely specialized to a given environment (subs, etc), or far more fragile than any mech (VTOLs).

Regarding that last point, have you ever tried to kill a Stinger or Locust in a single salvo? We see them as being easily squishable, but that's because most games are predominately populated with medium/heavy/assault mechs, and even those usually need to focus their entire attention on a Bug for at least a turn to bring it down. From other lights or light vees or ghu forbid, infantry? The kind of stuff you actually send on boring patrols or long-distance scout missions? Infantry can be killed, vehicles can get parked or side-critter, air units can get lawn-darted...but unless you're packing big boy firepower, I can almost guarantee that Stinger will survive the surprise first salvo and get a chance to run away and/or report your position. And that's what a scout's speed is for. It's not too race forward and find the enemy. It's to find the enemy, and race backward to live long enough to  report the contact.

[Getz]

While it might screen off Locusts, and Spiders, I would advise against trying to use them to keep P-Hawks away. For one thing, it means that that mech might be within firing range of the Shadow Hawks, and Griffins. For another, P-Hawks can handle them in short order.

For all the fact that a P-hawk can very well tackle either of the lights I mentioned, do bear in mind that I would be perfectly happy to lose the light if it either:
a) did sufficient damage to the P-hawk, such that the heavier mech that it was escorting can no casually finish the P-hawk off with it's own shooting, or;
b) ties up the P-hawk for long enough that the escorted heavy mech can either get away from the immediate danger or perform whatever function I wanted from it unmolested.

Naturally, if I wanted to take on a P-hawk and win I wouldn't assign a light mech to the task at all, but if I simply wanted speed bump intended to slow down something trying to interdict my main force, then an inexpensive light mech is well suited to the job.

[Minemech]

 While the Commando does have a fantastic theoretical damage tally, it rarely inflicts it. One of its primary weaknesses is the armor placement to ammo placement risk it takes.  This causes the Commando to be easy prey to mechs fielding Large Lasers, or PPCs.

[SCC]

We have rules detailing the costs and repair modifiers, and there are actually a couple of exponential effects to cost, although most of the costs are indeed linear.  A faster 'Mech pays more for its engine, and possibly gyro, than a slower 'Mech of comparable tonnage, but speed increases for heavier units require massive and prohibitively expensive engines and correspondingly larger and more expensive gyros.  A Locust pays a far lower base cost for its 160 rated engine than an Atlas does for its 300 rated engine, and that cost rises exponentially with engine size, not linearly.  There's also a final cost modifier based on tonnage, so even after the larger engine, bigger gyro, and other factors are taken into consideration, you still have a higher cost modifier for the sum of those components merely because they're for a larger 'Mech.  The 20 ton Wasp or Stinger would pay a +20% final cost modifier added to the sum of the individual components upon final assembly due to tonnage, but an Atlas would pay a +100% cost increase for EVERY component due to its 100 ton frame.

The problem is that the formula's we have are FASA-era nonsense, don't put any stock into them

Armor repairs cost the same for the same amount of damage, regardless of tonnage.  Replacement actuators and other internal components do cost more for the larger 'Mech, although weapons don't.

My point is that those costs are trival to some unseen and unknowable cost of actually building a 'Mech

This, very much. No matter how cheap a conventional vehicle is, no vee can ever match a mech's ability to traverse almost any terrain in almost any weather, and those that can are either extremely specialized to a given environment (subs, etc), or far more fragile than any mech (VTOLs).

True, but if compare the amount of armor that VTOL's carry, or rather can carry if well designed.

[Cannonshop]

The problem is that the formula's we have are FASA-era nonsense, don't put any stock into themMy point is that those costs are trival to some unseen and unknowable cost of actually building a 'Mech

True, but if compare the amount of armor that VTOL's carry, or rather can carry if well designed.

very FEW VTOLs in canon are actually well-designed, and this is in spite of rules-changes to make the truly awful one minimally viable.

There are, by contrast, relatively few (as a percentage) 'mechs that are absolute garbage-even in the light classification.

(even a lance of ALM Fireballs mixed with urbies can, in fact, be used intelligently.  This is somewhat to completely untrue of, for example, the yellowjacket.)

[Daryk]

I believe you yourself commented that they could be used intelligently... as spare parts! 

[Weirdo]

They're great for weeding out enemy agents in the quartermaster corps.

[SCC]

They're great for weeding out enemy agents in the quartermaster corps.

To a certain extent so are light 'Mechs, just look at the Locust LCT-1M.

[Arkansas Warrior]

Pro: Easier to replace when a Hunchback blasts clean through their center torso in one shot.


On the other hand, an AC20 to the center torso doesn't core a Warhammer, it just pisses it off.

[Wolf72]

Pro: Easier to replace when a Hunchback blasts clean through their center torso in one shot.


On the other hand, an AC20 to the center torso doesn't core a Warhammer, it just pisses it off.

pffft, my WHM center torso just screams to be critted ... at near 18 hexes by an AC-5.  enough about my bad luck.

I would think that during many eras of play, you took whatever was available.  Light mechs die quick, as do vehs. Better mechs are rarer due to attrition of production.  This isn't rock-paper-scissor anymore -- It's how many rocks, paper, scissors do you have at each mission.  Just don't invite WoB, they're poor winners.

[edit: bad to post near bedtime; I'm not sure I added anything to 'Advantages of Light Mechs']

[SCC]

Pro: Easier to replace when a Hunchback blasts clean through their center torso in one shot.

The thing is we don't actually know this, there's some sort of in-universe limiting factor on 'Mech production and it's not reactors. My personal theory/headcanon is that it's something in the control system, likely to do with the neural connector especially given that ASF are also seemingly affected, this actually makes the whole-head ejection system of the Hatchetman very nice as it may well save that key hard-to-replace component.