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    Default Mid-mount versus rear mount

    We are getting ready to repalce a 1989 E-1 rear mount. We are looking at mid-mount ladder towers. Looking for thoughts on benefits of mid-mount vs. rear mount. Height is not an issue. I think mid-mounts are more flexible for fireground ops such as putting master streams down low. Big concern is getting around overhead wires and 2 & 3 story homes fairly clsoe to the street.

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    Chief it sounds like you're in the same boat we were just a few years ago. We ended up replacing our rear mount ladder with midmount tower. We're very pleased with the result. We were convinced of the tower/platform and then had to decide on the rear vs. mid type. We really did not want the bucket hanging out over the cab reducing visibility and also have some large low hanging tree branches in town, so the decison was not too difficult. Certainly one of the big issues is street congestion. The MM's are not as manuevable as a rearmount, but we've found that we decent driver training and practice you can get just about anywhere. That being said we are probably resonding a few seconds slower as our drivers have to be more conscious of the rear of the truck due to "tailslap". During our research we found not all midmounts are equal and some have much greater tailslap than others.

    Having just completed a second three day aerial ops hands on program with Mike Wilbur, we really are seeing the advantages of the midmount with regard to setting up to cover two walls, the ability to put the bucket on the street, not only for storefront fires, but also to remove occupants to the street. In our downtown area a rearmount would have little chance of reaching the ground due to street/sidewalk width and parked cars. One thing we very very happy we did was eliminate the raised roof, which dramatically cuts into the scrub area when you are operating forward of the turntable (over the cab). We found the raised roof wasn't necessary as there really is no need for our personnel to ever have to stand up in the cab.

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    Quote Originally Posted by ChiefErickson View Post
    Height is not an issue. I think mid-mounts are more flexible for fireground ops such as putting master streams down low. Big concern is getting around overhead wires and 2 & 3 story homes fairly clsoe to the street.
    Hey there Chief. I would only say that a MM has an effective range of about 120 degrees (60 on each side) that it can get to the ground. Over the cab it may only go down to 45 degrees elevation.

    A RM has OVER 180 degrees (more like 210 degrees) in which it can touch ground and over the cab it will probably lower to around 7 degrees elevation.

    Just these elevation and rotational stats point to easier placement at the scene with a RM in my opinion.

    MM’s are heavier, longer and the departure angle on the rear as well as the tail slap creates many problems. You will also pay dearly for a MM design over a RM. I have seen departments get MM’s for simply a “style change” (not saying that is what you are doing). Others get them because they want to look like a larger Department.

    The slightly longer ladder section on a RM getting "under" or down low at close ranges (under wires as you have said) can most of the time be cured with proper placement training.

    The whole idea on a MM is reduced travel height – if that is not an issue, stick with the RM and have the gents stop 10’ back from the stop lights. TL

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    There is a huge trade off in that 3 section boom of the rear mount 100' How far away is the bucket when it finally gets to the ground? We did it coming off the rear of an E-1 with only a very slight grade in our last truck class and we were extended 100 with the main still over our heads. Our MM touches the ground fully retracted. I'm sure height might not be an issue in the station, but it might be with low bridges, trees and wires. I'm biased toward the mid, but I would suggest a head to head comparison in your district and see for yourself what kind of limitiations you have.

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    I saw the Crimson rear mount at FDIC. Their rear mount bucket can touch the ground fully retracted. It was impressive. Our LTI ST-2000 has to be almost fully extended to touch.

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    Quote Originally Posted by Halligan84 View Post
    There is a huge trade off in that 3 section boom of the rear mount 100' How far away is the bucket when it finally gets to the ground? We did it coming off the rear of an E-1 with only a very slight grade in our last truck class and we were extended 100 with the main still over our heads. Our MM touches the ground fully retracted. I'm sure height might not be an issue in the station, but it might be with low bridges, trees and wires. I'm biased toward the mid, but I would suggest a head to head comparison in your district and see for yourself what kind of limitiations you have.
    This is a photo of a 100' KME MM platform as it touches the ground fully retracted !...
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    thanks for the input. Sound advice

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    Quote Originally Posted by SSIaerialmanTIM View Post
    Over the cab it may only go down to 45 degrees elevation.
    Our ALF = 26 degrees over the non-raised roof. (without the cab avoidance)
    KME Spec on our truck = 21 degrees over the non-raised roof.
    E-One = 53 degrees

    Like TIM says you can place a RM at the sidewalk objective with proepr placement, but you lose alot of scrub above that point because you have to be further away. We have a congested downtown area where we felt it was criticcal to be able to both sit on the sidewalk and go up to the fifth floor. I'd like to see a rearmount floor 1250 gpm at full extension from the sidewalk while the gun is between 45-60 degrees to the bucket as would be required.

    There is no way a rearmount can have as much scrub as a MM of comparable length. Basically the added boom section allows the MM to operate closer to the body so if you were to measure sqaure footage of aerail coverage the MM would easily get to more locations.

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    Quote Originally Posted by Halligan84 View Post
    There is a huge trade off in that 3 section boom of the rear mount 100' How far away is the bucket when it finally gets to the ground? We did it coming off the rear of an E-1 with only a very slight grade in our last truck class and we were extended 100 with the main still over our heads. Our MM touches the ground fully retracted. I'm sure height might not be an issue in the station, but it might be with low bridges, trees and wires. I'm biased toward the mid, but I would suggest a head to head comparison in your district and see for yourself what kind of limitiations you have.
    I can't speak for the RM's, but one evaluation criteria in our 100' MM search was the distance it takes to place the platform on the ground at a 90 degree angle. We took the measurement from the side of the apparatus body to the front of the platform. The KME pictured earlier in the thread along with the Pierce and Crimson are about 26-30 feet. The Sutphen SPH100 measured 47 feet.
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    Last edited by Command6; 08-04-2007 at 10:35 AM. Reason: add photo

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    Quote Originally Posted by SSIaerialmanTIM View Post
    MM’s are heavier, longer and the departure angle on the rear as well as the tail slap creates many problems.
    Not to nit-pick, but not all mid mounts are heavier. Aren't Sutphens typically about 10,000-15,000 lbs lighter than any other manufacturer? I think they're actually lighter than a rear mount straight stick quint, let alone a tower. Their website says a 100' midmount quint has a 62,500 GVW. I bet a comparable rear mount probably is at least 75,000 GVW. Out here in Washington where axle loading laws are probably stricter than any other state, weight might be the single most critical issue when it comes to a large ladder truck.

    Obviously all of the other issues you raised still apply to them, though.

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    The KME pictured earlier in the thread along with the Pierce and Crimson are about 26-30 feet. The Sutphen SPH100 measured 47 feet.
    True, I was referring to the 5 section models which you pointed out, Pierce, KME and ALF. The 4 section designs from Sutphen, Ascope (95') and E1 take considerably more room. It was a major evaluation point for us too, the 5 section gives many, many advantages in tight quarters.

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    Thumbs up

    If I understand correctly RFDACM02 you would want the RM to flow 1250 with the ladder at full ext. with the bucket very low - say neg. 6 degrees elevation? With the monitor at 45 to 60 degrees UP?

    Did you mean to say full retraction?

    If you did mean to say full retraction, that is doable for some RMs as GFPD & Command6 said.

    On one other point I know of no aerial platform right now that the Mfg allows the monitor to travel more than 45 degrees up as a standard, but I may have missed one.

    If I had to do what I think your objective is RFDACM02, from a RM platform, I would simply position a little further away (say 15 – 20 feet further away than I might position a MM platform) - I would position so I was working the aerial off the rear corner of the truck. Then I would raise straight up, rotate off the back, lower under the “wire area”, extend as needed, point the monitor up and flow it.

    OH, keep in mind that extra 15 or 20 feet away could save someone's ***** if things get really hot like they did for the guys in that video here on Firehouse not long ago -the ones who ended up moving thier MM before it was stowed, guys in the bucket and all.

    Chief, whatever you buy – RM or MM, make SURE the Mfg allows the monitor to flow above grade at least 30 degrees and preferable 45 degrees if yo want that, as in RFDACM02’s example. Not all Mfg’s will do this. TL

    Quote Originally Posted by OneL1L View Post
    Not to nit-pick, but not all mid mounts are heavier. Aren't Sutphens typically about 10,000-15,000 lbs lighter than any other manufacturer? I think they're actually lighter than a rear mount straight stick quint, let alone a tower. Their website says a 100' midmount quint has a 62,500 GVW. I bet a comparable rear mount probably is at least 75,000 GVW.
    So true OneL1L, once again Sutphen proves they use AL and proper engineering to hook it up right. TL

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    Talking

    On the bright side ChiefErickson, hot life-sized “card-board-cut-out” beer sales chicks don’t care if it’s a RM or MM. TL
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    Last edited by SSIaerialmanTIM; 08-05-2007 at 12:26 AM.

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    Quote Originally Posted by SSIaerialmanTIM View Post
    If I understand correctly RFDACM02 you would want the RM to flow 1250 with the ladder at full ext. with the bucket very low - say neg. 6 degrees elevation? With the monitor at 45 to 60 degrees UP?

    Did you mean to say full retraction?

    If you did mean to say full retraction, that is doable for some RMs as GFPD & Command6 said.
    I meant at full extension flowing water 45 degrees to the side of the bucket with a slight upward angle (shouldn't have to be to extreme). Given the MM can be positioned in the center of a storefront and work both directions with pretty much full reach it shines in congested areas. The rearmount will have to be positioned short or beyond the centerline to cover the same distance and this will require the off the centline angle to be less increasing the angle need to turn the gun into the storefront.

    I may have sounded a little harsh on the rear mounts. They certainly are good when height is not a factor and setbacks are longer. But if you call a boom section 20 feet long this reduces the overall ability to be perpendicular to the objective by a story! Due to setback. According to my chart: If you need to be 20 feet further away you lose about 10 feet in working hieght. Rated height in the parking lot means little compared to how high up a wall the bucket can reach.

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    Quote Originally Posted by RFDACM02
    I meant at full extension flowing water 45 degrees to the side of the bucket with a slight upward angle (shouldn't have to be to extreme). Given the MM can be positioned in the center of a storefront and work both directions with pretty much full reach it shines in congested areas.
    I catch your meaning here, but both MM & RM can flow from 45 to 90 to the side of the buckets without compromising rated capacity (the quality manufacturers anyway).
    Quote Originally Posted by RFDACM02
    The rearmount will have to be positioned short or beyond the centerline to cover the same distance and this will require the off the centline angle to be less increasing the angle need to turn the gun into the storefront.
    True, but see quote 1 above – not a problem.

    Quote Originally Posted by RFDACM02
    But if you call a boom section 20 feet long this reduces the overall ability to be perpendicular to the objective by a story! Due to setback.
    True, a RM’s optimal working position is off the rear 180.

    Quote Originally Posted by RFDACM02
    According to my chart: If you need to be 20 feet further away you lose about 10 feet in working hieght. Rated height in the parking lot means little compared to how high up a wall the bucket can reach.
    I agree, but we are talking 100’ aerials here so even the RM being positioned a bit further away will still reach up the wall equivalent to say 6 or 7 stories.

    I drew up a little scenario showing what I was thinking. And I want to bring up the point of:
    1.) Drop Zones. Notice how small the drop zones are for the MM and one of them is likely too close to the fire to use. Notice the larger drop zone choice of the RM.
    2.) What IF the fire catches the next building (as designated by the blue flames in my pic)? This is where the MM is now in trouble. The operator of the MM may not have considered this and now the fire is too far forward of his operating range to fight. This is inherent due to MM positioning – FF’s are always taught to work right off the side on them and they position accordingly. Whereas I have always taught the RM driver to drive past the fire and work off the back. In my scenario the RM will be able to hit it without moving the truck. Just my point – The RM has more range simply due to less body obstruction around the rotational circle. And then there is the heat zone - MM are more likely to get caught in them simply due to positioning requirements or prefrences. The RM tends to be backed off a bit.

    3.)
    I’m not being hard on the MM – I like them both, but it’s useful to show all the points each one exploits over the other for the readers benefit. I would say both will do the job in my opinion, it just depends on the operator’s understanding of his machine. All good points to consider on both sides for Chief Erickson! Good discussions. TL
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    Good info Tim. The only point I have given your scenario and specifically #2)is that if the MM angles the cab just 25-30 degrees off center away from the building they can swing the boom around in a much wider arc. Our personnel are taught to always turn away from the working side at the last minute to gain scrub area in the direction of the cab. And in the blue fire scenario the RM will only be able to take defensive action as the boom will have to be raised to put any water on the fire. But alas, either would work well under the direction of someone who knows how to properly position the aerial for the work.

    Another thing to consider on either type truck is the configuration of the bucket. Many are still being built with retangular buckets that do not make them too user friendly. Those that have angled front corners and entry doors at the corners tend to be easier to place at an objective and certainly better at multiple objectives from the same set. Worst of all are those with no lip edge or just a front lip which makes it imperative to come into an objective straight on when trying to effect a rescue.
    Last edited by RFDACM02; 08-05-2007 at 09:18 PM.

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    Post To : RFDACMO2

    Do you know how many Jacks, Outriggers, & front under bumper jack ,on a 75' ALF/LTI Midmount platform apparatus ? Thanks, NJFFII

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    Quote Originally Posted by NewJerseyFFII View Post
    Do you know how many Jacks, Outriggers, & front under bumper jack ,on a 75' ALF/LTI Midmount platform apparatus ? Thanks, NJFFII
    Two Outriggers, two down-riggers, and a set of bumper jacks

    Chief1FF

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    Post To:Chief1FF

    Quote Originally Posted by Chief1FF View Post
    Two Outriggers, two down-riggers, and a set of bumper jacks

    Chief1FF
    Do you have a 75' ALF/LTI Midmount Platform at your department, if so can you send me a " PM " !.. Thanks, NJFFII

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    Default What type aerial???

    Quote Originally Posted by SSIaerialmanTIM View Post
    On the bright side ChiefErickson, hot life-sized “card-board-cut-out” beer sales chicks don’t care if it’s a RM or MM. TL
    I am guessing that is a Smeal platform? I think they are one of the few that uses the top railing over the access doors.

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    Quote Originally Posted by NewJerseyFFII View Post
    Do you have a 75' ALF/LTI Midmount Platform at your department, if so can you send me a " PM " !.. Thanks, NJFFII
    NJFFII,

    I do not have a one at my department.

    Elizabeth, Jersey City and Lambertville have them. Elizabeth's and Jersey City have been in service a couple of years and Lambertville just got their's don't believe it's in service yet.

    Chief1FF
    Last edited by Chief1FF; 08-07-2007 at 01:17 PM.

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    Quote Originally Posted by Command6 View Post
    I am guessing that is a Smeal platform? I think they are one of the few that uses the top railing over the access doors.
    Good catch 6, I missed the second gate (was there an aerial in that picture?) This was one of the contention points we had with the Smeal/Ferrara towers. We wanted only one action to open the buckets doors inward for rapid egress from the roof or building.
    Lots of little things to weigh out in a purchase this big. Our philosophy was that we could not make sacrifices that would adversely affect the tactical mission of the truck. The only real thing we were not able to have was two outriggers vs. four. Basically the Scope and E-One were the only trucks that could give us this and one failed on many other points and the other was $100K+ above the pack and still was short on most of the options.

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    Default Outriggers

    On the subject of outriggers, I have seen a variety of designs. The verbage is also confusing. P calls theirs stabilizers. Then there are outriggers, and jacks.

    We also considered the outrigger jack spread an important factor because of narrow streets. While Sutphen had only two outriggers on the SPH100 (and two underbody jacks), the footprint is about four feet wider than some with four outriggers.

    It looks to me that E-One has the best compact outrigger design on their 95MM; low profile and narrow spread. But then that is only one factor of hundreds in the equation as you alluded.

    It would seem that ALF had the most comprehensive design with the added front bumper jacks. Their design should remove nearly all the weight off the suspension and be rock solid.

    So what did you purchase?

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    C'mon 6, give me a break or a brake!

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    We purchased a 93' ALF MM. We too thought the E-One jacking system was the best, but unfortuneately there were too many other issues that detracted from the final product. Almost every bidder's truck had some feature that we wished we could incorporate. We went with the bid that closest matched our performance and itemized specs.

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