The U.S. Air Force announced today that it will be using the Boeing HH-47 as its new combat search-and-rescue helicopter, starting in 2012. The HH-47 is a variant of the CH-47 Chinook, “the only aircraft that can have a mid-air collision with itself.” This machine was designed in the late 1950s, first flown in 1961, and first used by the U.S. military in 1962.
There were a couple of competitors for this $10 billion program. They had the advantages of fifty years of improvements in engineering education, an average rising IQ, modern computers and computer software for simulation… and they lost to a group of engineers who grew up driving Model T Fords.
To go almost completely off topic, lacking a tail rotor, how do these things steer? I’m assuming the rotors are normally kept in sync?
I think you’re falling victim to survivorship bias. The list of failed/dead/extinct projects from the same era with similar engineering team pedigrees is rather long.
A complete over simplication on your part.
This is not quite your father’s bird.
Or would you rather they spent billions on a totally new concept that would take years to field?
Former: Shadow->LHX->Commache engineer ( I did help spend billions on a totally new concept that took years NOT to field!)
From the Boeing website: http://www.boeing.com/rotorcraft/military/hh47/index.html
HH-47 Capabilities
* An affordable, low risk, highly capable platform with a proven operational and logistics track record; compliant with key performance parameters and incorporates the advanced functionality to perform demanding CSAR missions
* Multi-mission capable platform with significant combat experience, at high altitudes, in austere environments and with limited visibility
* The Air Force CSAR version will be a new build aircraft that meets all Block 0 requirements and will require minimal upgrades to meet Block 10 requirements
* Key features include a net-ready cockpit, forward-looking infrared radar, terrain-following-terrain avoidance radar, and in-flight refueling capability
* Improved power, avionics, vibration reduction and transportability enhancements will also distinguish the HH-47 CSAR-X model
* Improved digital maps, greater situational awareness, mission planning and management capability enable flight crews to conduct missions with pinpoint accuracy
* In use by military worldwide including the Netherlands Air Force, United Kingdom’s Royal Air Force, Egyptian Air Force and the defense forces of Singapore, Japan, Australia and many more
Program Status
* Boeing’s offer was submitted in November 2005
* A flight performance and cabin suitability demonstration was completed using two MH-47Gs leased from USSOCOM
* An Air transportability evaluation was completed in December 2005 that demonstrated the ability to prepare the HH-47 for strategic airlift and re-build it to a flight worthy configuration in under three hours at each end
* Proposal effort is currently in the Evaluation Notice (EN) phase
* Source select announcement is expected August 2006 with a stated Initial Operational Capability of 2012
* If Boeing is selected, the HH-47 would be built at the Boeing Integrated Defense Systems’ rotorcraft manufacturing facility in Ridley Park, Pa., home of Boeing’s MH-47G Special Operations Chinook program
* Competition is the Sikorsky S-92 and Lockheed Martin / AgustaWestland US-101
Seems you are over-simplifying.
The HH-47 is derived from a fairly recent update (the CH-47F) to the original design. The engines and avionics are up-to-date. As a guess, I would bet the aerodynamics of the rotors have improved since the original 1950’s design. The airframe is an update from the original design.
That does not leave a lot of room for a competitor to offer improvement. It’s not like we discovered any fundamental new principles in aerodynamics in the last 50 years. Engines and rotor blades are probably the areas of biggest change, and I would bet the HH-47 is using current designs for both.
(Not a lot of information on the Boeing site – at least that is obvious.)
Here’s what the guys at Rotor and Wing magazine had to say… “In a move that stunned most observers, the U.S. Air Force has picked Boeing’s CH-47—an aircraft that dates back to the 1960s—over AgustaWestland’s EH101 and Sikorksy’s S-92” and “The Chinook was widely viewed as too big and noisy and of too old a design to stand a chance in the Air Force competition.”
Guys, Philip did not say the Air Force made the wrong decision. He’s right to note the airframe design is positively ancient. And yes of course they up-engined it and redid the avionics. Doesn’t change the type of helicopter.
Any effort at lowering the effective radar crosssection? Doesn’t look any more stealthy (as compared to say the Comanche, which allegedly had a smaller RCS than a Hellfire missile)
What about the tilt rotor technology we spent billions developing for the V22 (and V15 testbed before that)?
Preston, I am not sure how I am oversimplifying. I think the rest of your comment somewhat supports my point and I concur with your post. To me the original post was like comparing a car of 2006 with a car of 1950 because it had 4 wheels and doors. Hey, I was surprised, it can carry a lot, but twice the rotors is very loud and lots of flight critical stuff to hit with ground fire.
Regards tilt technology, I have never felt comfortable with that design, the complexity of the transmission which is required by the failure modes is not something I’d like to fly on a daily basis. Of course the CH/HH-47 has more than a few engines and rotors and ….is not the simplest / cleanest design out there.
It will be interesting to see how it plays out and deploys.
It’s all about the money.
Designing a new airframe costs tons of money. A new airframe would need to be tested and validated from scratch, this is not even taking into account all the crap bolted inside.
Now, take your pick from the current airframes in the inventory, pick the ones that fit the range/weight requirements. Then pick which one has the best maintenance history overall. That’s the one you strip down and use it as the basis for a “new” variant.
You end up with a helicopter that looks like the old version but all of its avionics and power plant are new.
This is not the first time, just see how the B-52 refuses to die. As for stealth, these helicopters are specifically requested to fill into a SAR role.
a bit more from the rotor and wing site.
The award is a remarkable endorsement of Boeing’s efforts over the last several years to reduce the cost of building and operating Chinooks, by redesigning key components. Those efforts persuaded the U.S. Army not only to rebuild existing Chinooks with the redesigned components but also to order hundreds of new-build ones, the first of which made its maiden flight in Philadelphia on Oct. 23. The Air Force is piggybacking on those cost-cutting efforts. Its order will require Boeing to expand its Philadelphia production line.
The contract covers the system design and development of the test aircraft and production of up to 141 operational ones, as well as related training and support systems, through 2019. The program is valued at $10 billion.
Compared to the Pave Hawks, the CSAR-X aircraft are intended to increase survivability, range, payload capacity, battle space awareness, and performance in adverse weather while decreasing mission reaction time. Program officials are seeking an initial operational capability by the first quarter of fiscal 2012. That capability is defined as five aircraft delivered to USAF’s formal training site and five to the first operational site, each set with the related training and support systems. For more, read the December issue of Rotor & Wing magazine.
Personally I find the “battle space awareness” comment the most interesting.
The reasons behind Frank Piasecki’s creation of the first tandem rotor helicopter with his XHRP-X ‘dogship’ are every bit as valid today as they were in 1944, following through to the H-46/47 family. No wasted energy going into your anti-torque tail-rotor (I mean really, that is sort of silly isn’t it? all that weight and engine power and the awful tail-boom always running into things)
Tandems have better approach,translation, hover in strong winds, are more manageable with interesting center of gravity configurations, the high-mounted rotor system allows for a spacious internal cabin for rapid ingress-egress of troops or cargo with large clearances from the rotors. A real natural for vertical replenishment, or operations from ships, or in the mountains.
In the H-46/47’s aspect, Preston is right. Since the debut of the gas turbine and advanced flight control systems, There have been no major breakthroughs for helicopters. About the only thing that modern H-47s have in common with their 40 year old forebears is the airframe configuration: Two turbines, transmissions and rotors on pylons up top, hang a fuselage/cabin that is little more than a box-car with flight controls and seats underneath. Cheap, insanely easy to upgrade, and maintain in the field.
These latest H-47’s benefit from integration with in-flight refueling systems, advanced flight control, improved transmissions, active vibration canceling systems, and you can pretty much just bolt on anything else that comes along. Swap out the turbines and rotors every decade for the latest incremental gee-whiz 10% improved products. Lather, Rinse Repeat for 40 more years!
Best visual representation of why the tandem-configuration is king for load and passenger ingress/egress in tight/high spaces.
http://www.defenseindustrydaily.com/images/AIR_CH-47_Afghanistan_Rooftop_Pickup_lg.jpg
First, the military has the training and maintenance infrastructure for the Chinook. I mean, they’re not buying one of these. It’s not a personal investment. The margin to be saved on cadre and established supply lines are phenomenal. If the number of Chinooks dropped, think about the number of people they’d have to retrain. That alone is easily tens of millions, if not hundreds of millions of dollars. Second, from a slightly inside perspective: I interviewed at Sikorsky a couple of years ago, and my sense was the Navy wasn’t too happy with their parts supply program. At least, they wanted me to help redesign the program.
What about the airframe *needs* to be improved? Let’s face it, airframe aerodynamics aren’t a big part of helo flying. I think it’s a testament to the airframe that birds built in the 60s are still flying. As an aside, yes, the gearboxes are mechanically coupled (http://www.chinook-helicopter.com/standards/areas/drive_train.html).
As for the AugustaWestland: no inhouse training cadre, no mechanics, parts from Italy?! As a cyclist, I can tell you the Italians make some beautiful stuff, but it’s on their own schedule.
As for any random reporter’s threshold for excitement that would merit use of the word stunning, well, c’mon. They have to write something to sell their rags full of ads.
The one think I would say is that it’s disappointing that the H-60 wasn’t in the running. God forbid all three services employ the same bird for the same function.
My dad worked on the original Chinook design. What I was told was “he designed the rear rotor assembly” but I’m fairly certain he didn’t do it single-handedly. 🙂 He had passed away before I found this out, so I never had a chance to ask him about it, but one thing I *do* know is that he never drove a Model T. He got his first car, a Volkswagen Beetle, after he returned from WWII, and at the time he worked on the Chinook was probably driving his all-time favorite car, a silver two-seater Jaguar which was well over half engine compartment from what I can see in the pictures. The only thing he regretted about having a kid (me) was having to give up that car.
Just had to set the record straight. 🙂
I got meet Frank when he was enamored of the idea of integrating the airship with the helicopter. Sad end to the only big blimp envelope in the Navy inventory as well as 4 old helicopters and the sad sad end to one of the pilots.
I was close to the x15 program at one time and was told of an interesting flight of 47 when max altitude flight attempt found that the ship would go higher sideways rather than straight ahead.
Hello guys, after reading your comments I found a few things to be interesting. First off I am a flight engineer in the US Army, and work on CH-47D. Although I’m not familiar with the different schematics for the HH-47 I believe it is safe to assume that most of its basic function is fairly similar. First off about the aero dynamics, You don’t want a helicopter to be aerodynamic, if you do it wants to fly and is hard to handle at a hover, therefore the Chinook has built in strakes, fins and a blunted tail to reduce its aerodynamics. They found this out with the A model, which had a wingshaped tail and no strakes or fins. Also just becuase an aircraft is multi engined does not make its design less viable. Actually most helo’s in the military inventory are multi engine. and ALL helo’s that are designated for heavy lift have at least two. It also doesn’t have the most rotors the super stallion (ch-53e) has 6 blades AS WELL AS a tale rotor. Tandem rotor helo’s, as mentioned, are much more stable platforms, they provide a better flight profile, easier hovering, higher altitudes, faster speeds. And as far as stealth, although its not going to win any awards on radar, you can’t say its much louder then most helicopters. Trust me, you can hear any of them coming from miles, and the loudest happens to be the Huey, due to the distance between blades.
As far as performance in the field, you just have to look at its tract record. In the army the Chinook is considered the workhorse, it has outlasted all of its contemporaries, and is not scheduled to be replaced anytime soon. In fact it is one of the cheaper airframes to maintain, the safest airframe in the Army, with one of the highest success ratios. Considering this proven record, why would anyone want to take a risk on an unproven airframe. Also as a SAR aircraft it has a much broader range then most other airframes. Considering how the Chinook has been used for every job in the army (including attack ACH-47A) there is absolutely no reason why the Air Force would NOT want to use it. Unless you consider Army Aviation less capable the Air Force?
Also there is a saying among Hook-ers, don’t fly on an aircraft you can’t carry your luggage in.
I just had to google “ACH-47A” I had never heard of this.
From the website: http://www.chinook-helicopter.com/chinook/gunsagogo.html
This quote of 2 ACH-47A in action in Vietnam.
On 22 February 1968, while participating in the big push to recapture Hue during the Tet Offensive, “Birth Control” received numerous hits from small arms ground fire while pulling up from a gun-run, and had to autorotate into the dry rice paddies about 600 meters northwest of the Citadel walls. Under intense fire, “Easy Money” came in and positioned herself between “Birth Control” and the advancing enemy, delivering suppressive fire while rescuing the downed crewmembers. As “Easy Money” was struggling to get airborne from the added weight, the aircraft received several hits which wounded some of the crewmembers near the rear of the helicopter. Once airborne and enroute to Camp Evans, the aircrew attempted to coordinate a downed aircraft recovery mission. However, before the recovery could be attempted, a report came in that the North Vietnamese Army (NVA) had walked mortars up to “Birth Control”, completely destroying the aircraft. Upon receiving the news, crewmember Walt Lacy responded: “She went out proud”.
The Army would not allow a single ACH-47A to operate alone and logistic transport helicopters were badly needed in the field. As a result, the experimental program was cancelled. “Easy Money” was transferred back to Vung Tau, where she served as a maintenance trainer with the in country Boeing Facility until the withdrawal of U.S. forces from Vietnam.
Having worked on the CH-47A and C models for the last 11 years of my military career, beginning in 1965 I can say Good for the US Airforce. as to the noise factor of the Chinook- it is far Less than the HH-53 series. As for the under-the-aircraft wind factor–once the aircraft is overhead there is almost no disturbance, the same cannot be said about ANY single rotor machine.The EH-101 has improved blade tip dynamics, but was still in development even after the Chinook had been upgraded to the D model. The upgrades on the Chinook include taking the parts off the airframe and replacing everything that shows any sort of wear-this includes the skin, and any structure found wanting that the skin is attached to, this is far beyond “changing engines and Rotary Wings”!. Keep in mind that C-47/DC-3 aircraft are still flying around the world due to the same procedures.