Army unveils new modified Chinook helicopter

Army News Service ^ | May 11, 2004 | Kelly Tyler

[Lee'sGhost]

Not really open to civilians. I was a journalist at the time (but don't hold that against me) and they were showing off their new toy. It was awesome. Every "window" was a video screen and the fuselage was on hydraulics. They added rotor vibration and sound affects. You couldn't tell it wasn't the real thing. That's why our pilots at almost every level are so good. They can get hours and hours of life-like training without ever spending a dime on fuel, maintenance, or even the craft itself.

[Dustoff45]

I'll fess up to about 11 months flying Hooks, with an 8 month 2nd tour in 'Nam. I was Flipper 45 with the 196th Assault Support Helicopter Company at An Son, Lane AHP in '69

I flew mostly the A Model - 2750 shaft horse power on each engine.

Since the rotors intermesh, they counter-act and cancel torque.

Controls remain the same, cyclic, collective and pedals. In this case right pedal would affect the forward and aft rotor heads differently causing the hook to rotate around a spot to the right. No tail rotor action, just forward rotor head to the right, aft rotor head to the left.

The model I flew maxed out at 33,000 lbs. We started a 2 hour duration of flight with 8,000 lbs. of JP4. Yep, that is 2 ton of fuel consumed each hour. After about 90 minutes into that fuel load, is when we could tackle the heavier sling loads.

The hook was really loud. They told us 120 decibels in the cockpit. The army fesses up to 112 decibels today. 85 decibels or more for 30 minutes or more equals permanent hearing loss. For me, as I go up the keys on a piano, eventually, I reach the point where I only hear the keys go clunk.

I really got off on how they used the '47 in some of those earlier missions in Afganistan. As I understand it, the BlackHawk did not have the capability to perform as well at the high altitudes.

The new rebuilt MH-47s are nearly a brand-new aircraft. They can strip down the airframe at the depot level, and do so much more these days to add avionic ability, extended fuel tanks, beefed-up drive-train components, etc.

For the rotor-heads that are here and have brought a single-rotor up to a hover, the hook is different.

1st step, a couple of inches of aft cyclic, add power and bring the nose and forward gear off the ground.

2nd, steady on the horizon, pedals and cyclic and add power to bring the rear gear up. Add collective to start the vertical speed, then just nose it over into transitional lift. Like most helicopters, the 47 takes more power to hover than to fly.

With an engine out at a forward location, we occasionally would roll forward and lift off with one engine, flying at best climb speed back to the unit for repair.

Maintenance sure did appreciate it when we saved them a trip to the boondocks.

I have flown TH-55s, (Hughes 269) H-13s, (Bell 47) UH-1H (Bell Iroquis), OH-6a (LOH Cayuse) and been in Bell Rangers. Nothing compares to the Hook, although I drool when the Marines go overhead near where I live south of Quantico with the Echo and later models of the CH-53

[Dustoff45]

We had two hydraulic actuators on each rotor head. With those we could move the swath plate through 360 degrees.

Were you ever on a flight where the SAS was disabled. every input was way too late, so you wallowed all over the place.

The SAS cabinet, and all that was in there made the pilots day go a whole lot better.

[Riley]

Very cool. I did Helicopter Support Team stuff (slingloads) with CH-53s in the Corps for a while- I remember loping away from the load on take off and being blown about three extra feet with every step. The racket was impressive.

Thanks for the twin-rotor lowdown- that answers pretty much what I was wondering.

[68skylark]

Very interesting. Okay, I only understood a fraaction of what you wrote, but it's still interesting! And thanks for your serivce.

[slohand]

Once a private replaced a couple of hydraulic lines in the cabinet. As the senior avioncs mech I was called in to program the SAS boxes because the aircraft was acting weird. I could not find out what was wrong. It turned out a couple of hydraulic lines were hooked up wrong. It took about a week to find out.

[windchime]

Bump!

[flymh47]

OK, here's how it works. I'm an active duty FE (flight engineer), and I'll try and keep it simple...
We have two rotor systems that counter rotate to cancel torque from the engines. Now the way this thing is different form an R-22 is that the rotor systems operate on differential collective thrust. That is when you put in forward cyclic, the fwd and aft heads add collective pitch, with the aft head inputting more than the fwd. So with the aft head producing more lift, you get nose down. Collective works the same, with both heads producing the same lift. As with roll, both heads tilt left or right. With yaw, one goes one way, the other goes the opposite. Pretty simple really, until you look at the flight control mixing bellcranks. Whoever designed that was a friggin' genious!! The good ol' "D" model is good for a max gross of 50000lbs, and the new 714A engines sport close to 5000 shp per side. She was (read still is...) the work horse in afghanistan. Nothing else is going to hover at 12-14000 ft, to put boots on the ground. And this MH-47G beast? Let me tell you...The Echo model is good, but I can't wait to get my Golf!!

[airborne]

I've jumped from a few. Greatest thrill jumping. You just walk out the tailgate and
F
A
L
L
!

[68skylark]

That does sound like fun. I hope I might have a chance to try that some day. So far my (very limited) jumping has just been from Airborne school -- some C-130's and a C-141 (plus a C-123 I was happy to get out of).

[68skylark]

I don't understand half of what you've written, but it's interesting anyway. Where else but FR could I get so much good information on so many different topics?

By the way, I'm asked a few people who haven't been able to tell me what the "M" stands for when used to describe a military aircraft, like this MH-47G. My only hunch is that the "M" seems to apply to aircraft often used for special operations work.

[flymh47]

sorry, i tried to keep it simple...MH=Multi-mission Helicopter...

[Chieftain]

I write maintenance training programs for a contractor for the US military. I wrote programs for 4 systems in the CH-47F, which only produced 3 birds, as they were intended for the USA regular forces. All the rest were converted to this 'G' model and it's everything the Special Ops aviators have dreamed of.

We have a retired Army SOF Chinook pilot in our group, his stories don't reveal a lot in terms of details, but they make your hair stand on end.

[68skylark]

sorry, i tried to keep it simple

No, there's no problem with your writing -- I just didn't understand a lot of your post because I'm not an aviation guy.

Thanks for the info about the "M" designation -- I don't know why, but it was bugging me to not know what it stood for. Take care & best regards.