Rear Vs. Mid Mount Tower Ladders

[x635 4,066]

For some reason, I can't remember what the benefits of a rear mount tower ladder is? (seriously). I saw one the other day and I couldn't figure out why a rear mount TL would be convienent.

I would think having that bucket hanging over the front would obstruct visibilty and reduce turning clearances? And aren't midmounts easier to position? Also, getting into the bucket is a lot harder I would think.

The pros of a rear mount......sets up like a regular rear mount? Shorter wheelbase?

[antiquefirelt 994]

For some reason, I can't remember what the benefits of a rear mount tower ladder is? (seriously). I saw one the other day and I couldn't figure out why a rear mount TL would be convienent.

I would think having that bucket hanging over the front would obstruct visibilty and reduce turning clearances? And aren't midmounts easier to position? Also, getting into the bucket is a lot harder I would think.

The pros of a rear mount......sets up like a regular rear mount? Shorter wheelbase?

I know that quite often the "tailslap" of the MM can make driving them in tight streets a little tougher. The amount of body behind the rear wheels can be very long and it's not hard to smack a car or street signs as you make a tight turn. Having the majority of the excess in front of you at least lets you see where your putting it. I know other RM proponents like the ability to nose in and set up with little rotational movement, where a MM might require 90 degree or greater rotation if you can't pull past or take the time to back in. Also I think the OAL is shorter on RM's in general as the length of the cab is used to eat up some aerial length, whereas the MM starts behind the cab? Of course most MM's have one to two more sections than standard three section RM's.

It would be easier for me to say what I don't like about RM's but of course I am biased, having a MM as my first due aerial.

[xfirefighter484x 234]

The pros of a rear mount......sets up like a regular rear mount? Shorter wheelbase?

Well, with all situations being different, aerial devices do not always only get used for vertical reach, but many times horizontal reach. With a midship mount, you can attain "maximum horizontal reach" only from 2 locations, off either side.

A rearmount can attain "max horizontal reach" off 3 locations, either side, as well as off the rear. Also, to attain maximum horizontal reach off a midmount, you have the entire length of the vehicle limiting the space you can get into, whereas a rearmount can back in to tighter spaces, and reach out further.

Yes, I realize you can back/drive straight in, a midmount and operate off the front or the back, but you do lose some degree of reach.

While operating at "below-grade"; A midship mount can only attain that off 2 sides, a reamount, off 3.

[Turborich 12]

(Insert seizure here)

It all theoretically comes down to 5 broad factors - response demographics, departmental SOP/ SOGs, scrub area upon initial positioning on district target hazards, surrounding mutual aid resources, and primary user preference.

I will now go consult my EAP..

[ddoyle195 8]

There is no question or debate, Mid Mount any day of the week!

(Insert seizure here)

It all theoretically comes down to 5 broad factors - response demographics, departmental SOP/ SOGs, scrub area upon initial positioning on district target hazards, surrounding mutual aid resources, and primary user preference.

I will now go consult my EAP..

[provfd 49]

(Insert seizure here)

It all theoretically comes down to 5 broad factors - response demographics, departmental SOP/ SOGs, scrub area upon initial positioning on district target hazards, surrounding mutual aid resources, and primary user preference.

I will now go consult my EAP..

And bay door height. MM wins that battle in many older fire houses.

[ny10570 745]

There is no question or debate, Mid Mount any day of the week!

OK, I'll bite here. Why? Assuming station space isn't an issue, how is a MM superior?

[x635 4,066]

I've never trained with or operated a rear mount TL before (except for Elmsford's Quint 2 in 1993), but I've seen many and been in the cabs of many.....doesn't the bucket obstruct visibilty somewhat? And, with some manufacturers, significantly? Also, I'd be worried about the clearance of the bucket overhanging in front when making tight turns or manuvers.

Thanks to everyone for helping me refresh!

[ny10570 745]

The visibility isn't so much an issue because most of the visibility you need is in the lower 2/3 of your windshield. Most rearmounts are similar to driving your personal vehicle with the visors down. Not ideal, but something you can deal with. The extra clearance you need to manage is easier because its in front where you can see it.

[16fire5 693]

OK, I'll bite here. Why? Assuming station space isn't an issue, how is a MM superior?

If your trying to line up the turntable with the objective its only a few feet behind you (the driver) as opposed to 35 feet away. I know someone is going to tell me that you line the bucket up with the victim but that is a far more infrequent occurance than trying to line the turntable up between the trees to get the throat of a building.

antiquefirelt I'm with you the new rigs have quite a bit of distance behind the rear wheels and make the art of driving them much different than a rear mount.

[ny10570 745]

16Fire, without a doubt accurate, but I'm not sure thats enough for provfd's mm any day statement.

[antiquefirelt 994]

When we replaced our aging straight stick we knew we were going to get a tower. Hands down, no question we felt that the bucket offered increased safety on numerous operations. The next question was MM or RM. We looked very hard and found the MM to be better for our application for a few reasons:

1. We have a narrow downtown district that requires the aerial length to be as short as possible to out it on the sidewalk or for use on lower floors. Maybe not the end of the world, but the ability to use the aerial master stream on lower floors at an upward angle was a big plus for our aging district where attached ordinary construction with considerable breaches between buildings rules the day. An aggressive knockdown could be the difference between one building and the block. MM's have 4 or 5 sections whereas RM often are only 3, sometimes 4, making the off the side distance far greater.

2. While you only need the lower 2/3's of the windshield for most of the driving time, the RM bucket obstructs your vision for viewing the fire building and slows positioning. Also, on crowded streets with lighted intersections seeing the color of the light can be handy to say the least. BTW, these observation are not just ours, we talked to tons of FD's about their aerials, likes and dislikes.

3. Station size issues: We couldn't fit most RM's in our 12 foot doors due to a slight grade on the apron. This in fact keeps our MM out of two bays on one end now and it's only 9'10" tall. (IIRC)

4. We didn't like having to climb up the rear and walk the length of the aerial with tools to access the bucket. With the MM, one guy climbs up and directly into the bucket and the second passes the saws and tools from the compartment adjacent to the access ladder. Small detail, but nonetheless was discussed.

5. Scrub area. While a RM can work of the rear at a greater length, it must be close to 90 degrees to the body before it can be brought to the ground forward of the turntable itself. This reduces scrub area. Short of being in an open lot where you can back in, most of our downtown requires a set close to perpendicular to the building face. The MM with the shorter aerial length excels at close in sweeping of the lower floors. Most of the time turning the cab just 20 degrees off the centerline on arrival allows us to either get two sides of the building or one long face from sidewalk to roof line.

This is not a knock of RM's merely pointing out the strengths we saw to the MM that effected our decision top buy one. Of course it helped that our hired consultant also suggested the aerial stick be replaced with a MM tower. But that was only the final nail in the coffin on other designs.

Edited January 29, 2010 by antiquefirelt

[provfd 49]

16Fire, without a doubt accurate, but I'm not sure thats enough for provfd's mm any day statement.

Not my statement, I just pointed out the height issue. ddoyle is the mm anyday man!

Edited February 2, 2010 by provfd

[ny10570 745]

Not my statement, I just pointed out the height issue. ddoyle is the mm anyday man!

I'm sorry about that. Come ddoyle. Where are you?

[x134 46]

(Insert seizure here)

It all theoretically comes down to 5 broad factors - response demographics, departmental SOP/ SOGs, scrub area upon initial positioning on district target hazards, surrounding mutual aid resources, and primary user preference.

I will now go consult my EAP..

LOL.....YOU FUNNY GUY TURBO!

[Guest alsfirefighter]

I've operated both and to be honest have never had a problem positioning either one. Currently my main dept. has a RM aerial and one of the reasons we chose that is we replaced a RM so our personnel were used to operating one, also with the rear overhang bottoming out with our hills was a major issue and we wanted a ladder tower. Each has its pro's and cons...MM you also lose a significant scrub area over the cab.

It all comes down to choice...you're going to be good with what you train with bottom line. I'm not so presumptuous to say one or the other as "hands down." For every pro of one...you can find a con. You have to make the right choice for your area, your operations and your personnel.

[16fire5 693]

MM you also lose a significant scrub area over the cab.

The scrub area issue can be minimized by angling the cab 15 degrees away from the objective if street width allows. Also for private dwelling fires if you pull the cab slightly past the house and line up the turntable to cover two sides the cab is totally out of the scrub area needed. But your point is good because situations can present themselves where the scrub area is less than optimum. I will point out that the addition of the enclosed cab the scrub area became further diminished when the apparatus is parallel to the objective. I mention this because some departments are refurbishing old single rear axle tower ladders which include new enclosed cabs which will reduce the scrub area they were used too.

I also percieve and I could be wrong on this but it looks like the turntable is higher off the ground on rearmounts. The lower turntable is to the ground the easier it is to operate under the ever present obstructions namely wires.