Q: There is some confusion about the heaviest variant in the FVL family, the “Ultra,” and the Joint Heavy Lift program. Can you describe how the two relate?
Answer: I mentioned earlier that Ultra is the “very heavy” FVL class, with a design payload target of 20-36 tons, with considerable interest in the mid- to higher end of that range. In capability terms, the Ultra corresponds to an aircraft concept known as Joint Future Theater Lift (JFTL). The JFTL developmental project was in turn based on a comprehensive body of Army work (known as Joint Heavy Lift) to establish a requirement and explore technology development for a large tilt-rotor aircraft capable of conducting vertical maneuver of medium weight forces (~30T) and aerial distribution to point of need, over theater distances.
JHL/JFTL (and Ultra) fulfill a mandated role for the Air Force to provide intratheater lift. As a result, JFTL definition was pursued from 2008-2012 under Air Force lead, in close collaboration with the Army. The effort produced a JROC-approved ICD in Oct 09 and was followed by a non-standard JFTL Technology Study (JTS) in lieu of an AoA. The JTS examined six different aircraft alternatives and demonstrated conclusively that the VTOL alternative provides the most operational effectiveness to the joint force for both aerial distribution and vertical maneuver. Following the completion of the JTS in 2012 and its approval by the AFROC, the entire initiative was terminated by the USAF.
• What is currently planned and programmed for the JHL program?
Answer: Although a JROC- approved ICD for JHL/JFTL/Ultra remains extant, the program is moribund. However, should the AF initiate an effort intended to replace its C-130 fleet or to introduce a new intratheater airlifter, JFTL should be viewed as the start-point and authoritative foundation for such an effort. The Army is continuing to explore the operational significance of JFTL in its concepts, wargames, and experiments, but it has no capability or standing to attempt to re-initiate an actual program of development without going through the Air Force. [NOTE: The same is true for the FVL community, which views JHL/JFTL/Ultra as falling fully under USAF auspices on the basis of “roles and missions”.]
• What do you see as its primary operational and strategic benefits?
Answer: JHL/JFTL/Ultra is primarily an operational-level, intratheater resource. However, it has the ability to self-deploy, with significant payload and can be employed to augment strategic airlift to move forces by air over considerable distances (>2100 nm, depending on weight).
The Army view is that JHL/JFTL/Ultra has the potential to provide the most dramatic benefits in utility and operational significance to the joint force and the Army for both vertical maneuver and theater sustainment. In multiple analyses, wargames, and studies over the past 8-10 years, it has eclipsed all other mobility capabilities investigated in terms of its positive operational impact. This impact, however, applies almost exclusively to the VTOL concept for the aircraft. STOL alternatives are judged to fall well short of the impact that can be achieved by heavy-lift VTOL. There are nine specific features of the HLVTOL JHL/JFTL/Ultra that distinguish its operational superiority. I’ll just refer to JHL/JFTL/Ultra as HLVTOL from here on for brevity.
• Superior Access with Proximity to the Objective. HLVTOL provides huge advantages in the future contest for access. The inescapable fact is that the ability to conduct vertical take-off and landing at extended ranges vastly opens up the land domain for vertical maneuver and sustainment. One recent two-year study of 14 countries (Global Deployment Assessment, Mar 10 – Apr 12) identified 48 million more VTOL landing sites than the relatively rare sites suitable for horizontal TOL. Moreover, even when contingency airstrips are used, the number of HLVTOLs that can employ in such an area exceeds that of fixed wing aircraft in terms of simultaneous presence on the ground and the number of times that an unimproved surface can be used before it has been degraded. [For example, a 3,000’ dirt-strip can support a single C-130 on the ground at any time, with limited re-use, while 10 Ultras with the same payloads could operate on the same airstrip for a near indefinite period of time.] A third major point is that the Ultra’s advantages in access mean that it can deliver forces and stocks in close proximity to the objective (within tactical range of an assault objective for immediate approach and attack or directly to the point of need for sustainment). This kind of flexibility and these kinds of options simply are not available for horizontal landing aircraft.
• Versatility and Agility (full ROMO). It is difficult to conceive of a future operation of any size for which the employment of HLVTOL would not have considerable and unique value above and beyond current fixed wing and rotary wing fleets. If fielded, HLVTOL would present major operational benefits across the entire range of military operations, including:
o Joint forcible entry operations (JFEO) via vertical maneuver of mounted forces from land or sea. The capability to introduce a highly mobile, medium-weight force for JFEO or subsequent intratheater vertical maneuver instead of light, tactically immobile, dismounted forces, represents a major break-through in maneuver capability.
o SOF direct action at extended ranges, without refueling, directly to objectives rather than to an off-set landing area.
o Non-combatant evacuation (NEO), with far fewer aircraft.
o Humanitarian assistance/disaster relief (HA/DR) into remote areas which are not accessible to fixed wing aircraft. Recent history has shown the difficulty of getting fixed wing aircraft into locations where they can support HA/DR and the same is true of short-range tactical helicopters.
o Aerial sustainment directly to the point of need, from land or sea bases
o Amphibious air assault well beyond the littoral
o Extended range anything (CSAR, MEDEVAC, CASEVAC, Fuel Cow, etc.)
• Augmentation for Strategic Lift. Because of its extended range, HLVTOL can be employed to move forces and stocks over distances in excess of 2,000 NM, depending on payload. Ultra is not a C-5 or C-17 substitute, but could augment the strategic lift systems for select missions.
• Operational Reach. Similarly, the unrefueled radius of action for the HLVTOL in operations such as vertical maneuver, NEO, or HA/DR can extend as far as ~1,000 nm, depending on payload.
• Ability to Achieve Surprise. HLVTOL does not rely on runways, dirt strips, or airfields which will often be occupied or under enemy observation. Vertical take-off and landing permit it to be used anywhere where there is sufficient, level or moderately sloped ground space (300’ diameter landing area). This feature, plus its ability to complete force closure very rapidly in proximity to the objective, enables our forces to achieve surprise against the enemy, which will almost never be possible with fixed wing aircraft, except for airdropped forces.
• Theater Distribution. As noted earlier, the verticality and range of HLVTOL permit it to carry out aerial distribution from theater support bases across the entire theater distribution network, including to small unit outposts, thereby reducing time-tables, ground force structure, infrastructure, and casualties. The aircraft can also be employed for aerial or ground refueling.
• Seabase Capability. Fixed wing aircraft sized to deliver HLVTOL payloads cannot operate from shipboard, but a VTOL aircraft can.
• Simplicity (relative to other options). Finally, the issue of simplicity should not be ignored. It has several facets. For example, when used in theater distribution, HLVTOL greatly simplifies that function by eliminating one or more node transits and mode transfers (air-to-ground, ground-to-air) and delivering directly to the using unit. For vertical maneuver using fixed wing aircraft, the AF first requires that unimproved landing areas or even first-use runways be certified before use, through a complex, overt, time-consuming process that forfeits surprise and may be easily denied by an alert adversary. In contrast, HLVTOL can be employed in an air-assault paradigm that requires only a few hours of covert preparations. For these operations, MOG is also a major problem for horizontally landing aircraft. They require more time, much larger areas, and often many different areas, which may be separated from each other by significant distances, to deliver forces of battalion size and larger. In contrast, HLVTOL can execute such missions in smaller areas, over shorter periods of time, with little fear of having degrading effects from re-use.
• What are some of the main technical challenges, and how can these be best addressed?
Answer: The biggest technical challenge is simply the scale (size) of the aircraft. VTOL aircraft, until we discover anti-gravity, have to generate vertical force. The best way to do this within the foreseeable future is via moving an airfoil through the air and generating lifting force. There are other ways to generate vertical force, but they are all operationally unsuitable in some way. Rocket thrust, jet thrust, or any other means of upward thrust creates unacceptable surface conditions. Buoyancy lift removes the surface problems but generates other problems with ballast control, altitude management, and slow speed operations. The most effective and viable means to accomplish the capabilities I have described earlier is via a large rotorcraft. We have looked at the many different forms of rotorcraft, and for the mission sets associated with JHL/JFTL/Ultra, tiltrotors dominant the solution space.
Tiltrotors are not new. There have been multiple experimental aircraft flown The V-22 is the first operational tiltrotor, and by the growing number of press reports we see daily now, is proving the military value that its visionaries’ and developers foresaw. We see the Europeans committed to developing a commercial market for tiltrotors. The AW609 is slated for full certification by 2016. So building an effective tiltrotor aircraft is no longer in doubt. Although, you will still find some skeptics, who are pretty out-of-date technically, that can’t disassociate their past perceptions generated during development problems, with the configuration in general. Or they will assume that some aspect of the V-22’s design, which they don’t like, is just an innate characteristic of tiltrotors. I guess such is the fate of all new product introduction.
The best way to address these skeptics and all the arguments they offer is to build an aircraft and show them it works, that it does what the designers said it will do. Legitimately, skeptics aside, in the case of JHL/JFTL/Ultra, there is a need to fly a scale representative vehicle. All rotorcraft, like all other aircraft, and for that matter all complex systems, are a combination of interacting parts. In the case of rotorcraft, the dynamic interplay of airloads, structures, response rates, control schemes, etc. is always a risk area. We understand much more of the physics of this interplay today than we did even a decade ago, but we are still on the front end of the fundamental understanding of all the interactions that happen in rotorcraft, such that we can design it right, the first time. That’s why, nationally, it is vital that the DoD and NASA retain our meager investment in rotorcraft S&T. But that’s a different topic for a different day.
The body of design work we did during JHL, which is the most definitive study of the technology and characteristics of such a large VTOL aircraft, leaves no doubt in my mind that we can build a successful tiltrotor at this scale. However, there is considerable risk that we can reach the levels of performance at the weights we project. JHL design takes into account the advances over the last two decades in rotors, drives, engines, automation, and subsystems technologies that the DoD and NASA have invested in. We didn’t go after any “unobtainium”. We took a realistic view of what could/should be achievable. But JHL is a technologically advanced aircraft design. Anytime you design any aircraft, there is risk. And the further away from past designs you get, whether in scale, configuration, materials, or approach, you create more risk.
In JHL’s case, scale is the biggest unknown. At the weights and loads associated with that scale, do the structural properties and dynamics hold their relationships as expected? This is more of an issue for the rotor and drive systems than the basic fuselage. We have built large aircraft before and know how to design large fuselage and empennage elements. We’ve built large wings and understand those characteristics. The tiltrotor wings are different though. They are stiffness driven and not just strength driven. When you put the pieces together, the biggest risk of a large, ultra heavy lift VTOL, is that weight doesn’t get out of control in order to maintain dynamic stability and control of the aircraft.
If you’ve ever seen a video of a rotor blade in flight, you probably wouldn’t be willing to fly anymore on helicopters. It moves in every direction you can imagine and even some that you can’t. That is all a function of varying loads and forces resulting from controlled input and uncontrolled forces coming from the external environment and unknown interactions. The resulting forces imparted to the aircraft, its structure and dynamic systems, and its control actuators and effectors have to be accounted for in their material properties. More force, generally means more bulk in the materials. Sometimes, these things don’t scale the way you expect them to. So, from my perspective, the effect of scale is the biggest risk.
There are other risks, of course. Different design approaches and technologies in all areas of the aircraft can be a significant risk. We know that there is significant performance improvement to be had in slowing the rotor system during forward flight. That reduces the compromise in twist between hover and forward flight conditions, thus making the overall design perform better in both conditions. How much variation we put in the design and how we go about that can create risks in the drive system, engine, structural resonance, control schema, etc. Whirl flutter is something that all tiltrotor designers worry about. That is when the pulsive forces from the rotor get too close to the natural frequencies of the wing and fuselage and bad things happen. The larger the variation in rotor speed, the larger the band of frequencies that have to be managed.
I could go on, but I don’t want to scare you into thinking that there are so many unknowns that we can’t design a new tiltrotor. I could talk about the issues associated with fixed wing design and identify as many risk areas, which would probably just scare you off of flying altogether. And we don’t want to do that. We need to fly and these are just the things that the people that design and build these aircraft deal with in every aircraft.
The best way to address all of these risk areas is to just go and do it. We need to design, build, and test a size representative flight article. We could do that any number of ways. My preference would be to take the JHL designs we have already done at the conceptual level, and use them as the basis for setting the overall aircraft requirements, architectures, technological approaches, and define a representative flight article. I would do some wind tunnel and ground rig testing during the detailed design and build-up process. But ultimately, the proof of what you think you know, is in flight. We don’t have to build a “prototype” in the sense of what that word means to the military. We could build a technology demonstrator or even an X-Plane version. It just depends upon how much risk you want to buy down for the next stage of development. We have been and are still ready to go do just this. I would certainly like to see the DoD take this step. We know the operational value that such a system would bring. If we could build a demonstrator, I believe it would convince most of the naysayers and the DoD would move out to realize the tremendous capability that such a system would bring to us.
Q: What are the consequences if the FVL program is not fully endorsed and sustained over the long run.
Answer: As noted earlier, FVL is in its 5th year of activity. If it fails, those 5 years of work are lost and a re-start is unlikely for at least 5 years after its demise.
But, the prospective failure of FVL should be viewed in a larger context. The first element of the larger context is the fact that the FVL initiative is the 4th joint effort in the last 15 years to attempt to establish a developmental pathway for “next generation” RW aircraft. Obviously, the three previous attempts failed. Why has this happened?
Those failures rest on common ground. The primary reason for the failures is the absence of high-level Departmental advocacy that is institutionally sustainable over the long term. Both of these factors – high-level advocacy and institutional sustainability – are key.
The second reason is that the DoD rotorcraft fleet is a divided family. Although all Services, SOCOM, and the Coast Guard possess rotorcraft, requirements and the timing of needs are different. As a result, it is difficult to define sets of capabilities that satisfactorily meet the requirements of all the potential users of a particular class of aircraft. In the past, the path of least resistance to meet individual Service requirements has most often been to pursue separate programs of record. Once those separate PORs are in place, they themselves become obstacles to joint initiatives, since no Service wants to see its acquisition programs (which meet current requirements) decremented or delayed as a means of funding joint programs that will not bear fruit until well into the future.
Finally, as the majority owner of the DoD fleet, the Army is the Service that has the greatest overall need for and can expect the most significant benefits from new RW aircraft starts. Upgrading its fleet represents a major acquisition program(s) over an extended period of time. In contrast, even though helicopters fill important roles for the Air Force, Navy, and USMC, moving to “next generation” RW technology will often be viewed as significantly less important than maintaining and improving fixed wing aircraft and ship-building. The Army will always have the most skin in the game and the most to gain; other joint stakeholders, in contrast, can generally be expected to be less invested in the outcome of an initiative like FVL or its predecessors.
Returning to the question of consequences, then, we can say confidently that the demise of the FVL initiative would:
• Return the developmental approach to a one that is Service-centric and more likely to perpetuate the current practice of upgrades and modernization, rather than seek new starts based on new configurations and technological innovation.
• Ensure that the DoD and private sector RW technology communities stagnate further, further degrading US technological standing comparative to others, and possibly leading to tech overmatch in this key area.
• Severely constrain the Army ability to operationalize and execute its future concept of expeditionary, distributed operations until well beyond 2035.
These consequences appear to be sufficiently severe to warrant extraordinary efforts to avoid them. At the very least, the Department should ensure that an effective funding stream continues to flow into the JMR TD activities to enable the maturation of the technologies needed to move from conventional helicopters to more advanced designs.
Q. The Future Vertical Lift (FVL) program is currently underway and aims to develop a new generation of vertical lift assets. Can you briefly describe this program, its scope, ultimate goals, and approximate timeline?
Answer: FVL has not yet achieved program status, but it is in the 5th year of activity as a major OSD initiative.
In essence, FVL is a joint strategic plan, initiated by Congress in 2008, approved by the DepSecDef in 2012, managed by an OSD/Joint Staff/Services Executive Steering Group, with implementation led by Army. The FVL Strategic Plan projects the long-term transformation of the entire DoD rotary wing (RW) fleet through the development of the “next generation” family of systems, across 4 “classes”: Light, Medium, Heavy, and Ultra. The plan recognizes that modernization and upgrades to current aircraft will be insufficient to meet future DoD vertical lift requirements. Central emphasis rests on a joint multi-role approach and commonality. Industry participation takes place through the Vertical Lift Consortium (VLC) which was deliberately established in conjunction with this initiative to improve the strategic planning collaboration between the government and industry.
The Army led the development and JCIDS process for JROC approval of the FVL FoS ICD in April 2013 and it retains lead at present. Activity is now focused on conducting analysis and preparation for a materiel development decision (MDD), unofficially scheduled for the end of FY15, followed by an AoA to be completed in FY17, to support a MS A decision to proceed with acquisition of the FVL-Medium. The current target timeline for FVL-M IOC is ~2034-35.
• The first development within the FVL program is the medium-lift variant. Simultaneously, the Army is conducting the Joint Multirole – Technology Demonstrator program. How does the JMR-TD fit into the larger FVL family? What is the current timeline for JMR?
Answer: JMR-TD is working to bring together the kinds of technology I talked about earlier in the discussion into technology demonstration flight articles. As a Tech Demonstrator, JMR-TD, will show that new aircraft configurations, populated with new technologies and design approaches, can result in a feasible materiel solution for a combination of vehicle performance requirements. It is not a “prototype” program. It won’t select the specific configuration that will be pursued for FVL-M, nor will it set the specifications for the FVL-M. It will, however, greatly inform both.
JMR-TD is on schedule for first flight in FY17 for two test articles. The JMR-TD includes two primary elements. First, and the one most people recognize, is the vehicle performance activity that is ongoing right now with the four industry partners, (AVX, Karem, Bell, and Sikorsky/Boeing). However, there is another effort, funded at a smaller level, which is addressing future mission systems technologies, including the open architecture electronic backbone that supports aircraft and mission systems. The mission systems work is really just now beginning and you will hear more about it in the coming days.
The vehicle development work, commonly referred to as Phase I, is centered around a Model Performance Specification (MPS) that was developed to reflect a set of performance requirements representative of what an FVL-M might entail. At the point it was issued in January of 13, it was our best thinking on what FVL-M might look like. That vision is, of course, changing over time and so the JMR-TD MPS was never expected or advertised as the definition of FVL-M. We took the thinking at the time and stuck a line to use as a litmus test to design aircraft around. At the end of the JMR-TD, we will know how close our projections of a future aircraft come to reality and what technical areas require the most attention in future development work.
The JMR-TD carries a design effort against that MPS. It also is building flight articles that will represent a subset of that MPS design. The combination of flight article, ground tests, and analysis will be the proof, or not, of the MPS designs. We learn a ton of things from this activity that will greatly improve our decision process whenever FVL moves into a real development program.
I should note at this point, that we consider the JMR-TD not uniquely peculiar to FVL-M. We chose the conditions for the JMR-TD such that we believe we learn things that scale to the “light” and “heavy” classes of the FVL family as well. Even some of the technologies will provide us information in support of the “ultra” class. So, although we centered the JMR-TD around a point-in-time thought about the FVL-M, the technology community will be looking to scale as much of the learning we can across the entire family of future vertical lift aircraft. We believe that the JMR-TD fits nicely with the anticipated schedule for FVL. The MPS design activity will support the ongoing FVL analyses in support of a near-term MDD and the actual aircraft development work will prepare us for the Tech Development effort following a MS A decision in FY18. Keeping the JMR-TD fully funded and on track is very important for the FVL activity.
• In your view, what are the prospects for the JMR program in the current budgetary environment?
Answer: I think they are excellent. The senior leadership of the Army and of Army S&T are committed to the JMR-TD. I’m really pleased with the bottom-to-top support I see in the Army for this S&T effort. The only risk I see for the JMR-TD is the risk of the FVL initiative stumbling. FVL is an extensive initiative with lots of moving parts. Anytime you try to take as large an enterprise approach as FVL represents, there are many opportunities for delays and conflict. If FVL were to become fragile or experience a significant delay over that currently planned, the Army could get some “weak knees” in response to extreme budgetary pressures. But I don’t see that happening anytime soon. The Army has really stepped up on the JMR-TD program, and I expect it to hold its ground in the foreseeable future.
It does point out though, that the Army needs to be more than fully engaged with the FVL initiative, the other Services, Joint Staff, and OSD. The Army’s equities here are huge and it is imperative for the senior leadership of the Army to be upfront and visible and leading the charge for FVL.
Q3. Many, yourself included, have argued that future rotorcraft need revolutionary gains in speed, range, persistence, and payload.
• What are the operational, tactical, and even strategic imperatives for these advances, and what role have lessons learned from Afghanistan and Iraq played in shaping these requirements?
Answer. The first thing I would say on this subject is that, because the term “revolutionary” can mean different things to different people, it’s not a term that I would choose to characterize future improvements in rotorcraft capabilities. Instead, I prefer to think of these advances as “leap-ahead”, or “next generation”, or even “break-through”, if for no other reason than they extend beyond the outer limits of what can be accomplished in the future with helicopters. In other words, we have to break through the constraints imposed by the laws of physics on conventional helicopters and adopt new VTOL configurations, which are not as severely constrained.
With respect to the imperatives for these advances, I have already discussed many of the operational- and tactical-level driving factors in my previous answer. I would further note that strategic imperatives include the overarching mission set prescribed in current defense strategic guidance (Jan 12), which also has a bearing on the capabilities of future rotorcraft. For example, that mission set includes deterrence, rapid force projection, counter-terrorism, counter-WMD, humanitarian assistance, and disaster relief. The requirement for rapid force projection in conditions of diminishing US strategic mobility capabilities and infrastructure highlights the benefits of self-deploying rotorcraft. [The Marine Corps has recently demonstrated the significance of this capability in the Philippines and Africa.] The other missions reinforce points I have made earlier regarding the expanding dimensions of future operations, their distributed and non-contiguous nature , the need to be able to maintain higher optempo, the expanding range of environmental conditions, and the ability to overcome access challenges, etc.
Regarding Afghanistan and Iraq, one of the most important lessons learned there is how universally relevant VTOL aircraft are to those kinds of operation and the degree to which they provide significant operational advantages with respect to reconnaissance, security, maneuver, aerial sustainment, aerial fires, rescue, and MEDEVAC. The deployed VTOL fleet significantly magnified force capability as a whole; had they not been present, troop numbers would have had to be augmented significantly to account for their absence. The experience also demonstrated the operational benefits that could have been achieved had the aircraft had higher performance levels with respect to speed, range, time on station, payload, and high/hot conditions. To cite just two examples: 1) even a modest increase in speed and range would have had a meaningful impact on MEDEVAC outcomes; 2) an improved capacity and payload capability for cargo aircraft, with improved range, could have reduced the number of ground convoys needed to sustain the force and carry out routine and emergency deliveries to remote company positions and combat outposts, while simultaneously reducing losses to IEDs.
• In what ways could a next generation family of vertical lift systems change the way the US Army operates?
Answer: I have not yet quantified for you the actual performance ranges that we have in mind regarding future rotorcraft. This question enables me to briefly do so to set the stage for my answer.
o Combat Radius: ~230 nm
o Speed: >230 knots
o Time on Station: As much as 2-6 hrs, depending on range to area of interest
o Payload: This attribute is essentially a fall-out from aircraft size and power, but the goal would be to design aircraft to account for mission-based, “pacing” payloads.
o Atmospherics: 6K/95, which corresponds to 12,000’ ISA
Given these improvements, their effects on rotorcraft unit employment can be described as follows:
• Significantly greater unrefueled combat radius to:
o Support the roll-back of an enemy anti-access regime
o Conduct joint forcible entry operations from land and sea-based platforms located in distant sanctuaries
o Conduct deep strike and vertical maneuver to operational depths
o Conduct aerial distribution to point of need across the breadth and depth of the battlespace
o Extend CSAR reach
• Increased speed to transit extended ranges more rapidly, reduce cycle time for assault and aerial sustainment, complicate enemy acquisition and engagement, and meet “golden hour” MEDEVAC metrics.
• Increased time-on-station (ToS) for aircraft performing ISR, escort, target acquisition/designation, CSAR, sonar distribution, maritime mine/countermine, and attack functions. Increased TOS equates to a higher “volume” of the function being performed, a higher level of simultaneity, more area covered, and reduced time periods when coverage is not available.
• Self-deployment capability for future RW aircraft to reduce the burden on strategic lift assets and provides a flexible employment option for force commanders in the early stages of conflict, an option which does not currently exist. This is an important consideration. If we have to use ships or strategic airlift (as it exists today and as the AF envisions it for the future) to deploy our assets, we are restricted to well developed, well-known, and fixed locations. The ability to self-deploy our RW assets allows them to go where they are needed, when they are needed. This is a huge aspect of becoming the expeditionary force that the Army desires to be.
• Capability to maneuver light- and medium-weight elements in assault configuration (internally-loaded, fueled, armed, with crews) for immediate employment, closing the force more rapidly.
• Execution of a “family of systems” approach that optimizes the distribution of payloads more equitably across weight classes, based on operationally-determined priorities.
• Expansion of the ability to operate in high-hot and high-cold conditions for appropriate mission segments, with larger payloads.
• Improved ability to operate in constrained urban spaces with UAS teammates and with the smallest manned system.
• Shipboard capability: ensures that future aircraft developed with a joint approach, can routinely operate from both shore and ship for maneuver, movement, and sustainment.
At this point, it would be remiss not to mention another capability improvement that would have major positive effects on all forms of RW operation, notably, significant advances in reliability, maintainability, and availability of future RW aircraft. The most significant operational benefit of this break-through would be at least a doubling of the optempo that can be maintained. In addition, this improvement would underpin reductions in cost, ground force structure, and operational uncertainty, while also freeing up aircraft to absorb a much larger share of force sustainment.
Q: Many future operational concepts focus on increased distribution of forces and growing anti-access/area denial (A2AD) threats. What are the primary challenges that future operational environments create for Army Aviation and rotorcraft more broadly?
Tenney: This is a very important question for two reasons. The first is that both Army and joint organizations engaged in research and analysis regarding future conflict agree that the operational demands of the future are changing dramatically. The second is that the developmental and fielding timelines for major new starts like rotorcraft are so extended – typically 15-20 years – that prudence demands that these aircraft are designed to meet future requirements, rather than just those that confront the force today.
A2AD is a big part of the calculus and to understand those challenges, we have to look at them in two parts – anti-access (A2) and area denial (AD).
To begin with, achieving assured access has three distinctive elements. Geographical access refers primarily to the ability to operate in remote locations with austere infrastructures, the best examples of which are Afghanistan and Africa. Political access addresses the question of whether or not US forces will be granted access to bases, ports, other facilities, and airspace under the sovereign control of our potential regional partners in a future conflict. The absence of political access, like that experienced in OIF when Turkey denied overland transit of US forces across Turkey into northern Iraq, creates huge problems with respect to timeliness of response and the distances that have to be traversed to reach the desired objective area. (In the example just cited, because the 4th ID could not be downloaded from sea in Turkey, it was forced to wait an entire month afloat, until space was freed up in the very limited port facilities in Kuwait.)
The third element is enemy anti-access (A2), which encompasses deliberate efforts by potential adversaries to deny the US air and maritime access, employing capabilities designed specifically for that purpose. China’s current and projected anti-access capabilities provide an excellent example of such deliberate efforts:
• Air and Ground: anti-ship ballistic and cruise missiles (launched from air and land), anti-ship strike aircraft, state-of-the-art integrated air defense, unmanned aerial systems.
An effective A2 regime will affect both the ability and timeliness of the joint force to get to the theater and, once there, to get into the fight. The Army faces the greatest challenges on these points, although the USMC will also find it increasingly difficult to mount amphibious or aerial operations from the sea in the face of an operational exclusion regime. When combined with the decline of U.S. global deployment infrastructure, these factors create conditions under which the start-point for entry operations may be hundreds of miles from the objective area, i.e., beyond the reach of all but a small part of the joint force.
The second component of the assured access challenge – area denial – is operative at the tactical level. Enemy capabilities for area denial include advanced guided rocket, artillery, mortars, and missiles (G-RAMM), which include improvements in range, precision, and lethality. The adversary will employ these capabilities under many conditions, but they will have particular value when used to deny known or easily identified landing areas and to engage US maritime forces operating in the littoral.
Collectively, the A2 and AD challenges place increased emphasis on ground and air capabilities for advanced mobility, speed, and range, which are further enhanced if a smaller logistical footprint can be achieved. The failure of the U.S. to achieve visible improvements in these areas has the potential to significantly retard an effective U.S. response in a crisis, thus undermining operational collaboration with regional partners while emboldening regional adversaries.
In addition to A2AD, there are four important trends, already observable in Iraq and Afghanistan, which are expected to continue to affect larger scale operations. First, and most importantly for aviation systems, the breadth and depth of future operational areas are expected to increase significantly in size. Second, the battlefield framework will be further characterized by non-contiguous areas of operations (AO), i.e. AOs that are separated from each other within the larger joint operations area (JOA). Third, the range of environmental conditions that the future force can be expected to confront will likely encompass more extreme conditions and more activity in urban terrain. Fourth, the nature of future threats will introduce operational complexity with respect to the ability of future adversaries to combine some high-tech capabilities with a variety of operational patterns (hybrid warfare). These conditions will drive new demands across forces operating in the land domain to expand operational reach with fires and maneuver, increase optempo, achieve situational understanding over larger areas, and simplify and reduce the logistical footprint required to support such operations (particularly important in austere areas).
[Side-note: Joint documents such as the Joint Operational Environment (JOE), Capstone Concept for Joint Operations (CCJO), Joint Operational Access Concept (JOAC), Major Combat Operations Joint Operating Concept (MCO JOC), and Army concepts like the Army Operating Concept (AOC) are all consistent with the points made above.]
Q: Some have argued that the pace of innovation for rotorcraft is lagging far behind that of fixed wing aviation. Do you agree with this analysis, and if so, what are its effects?
Tenney: Yes, I agree strongly that RW technology is lagging far behind fixed wing aviation. Frankly, the assertion is indisputable. FW systems are inherently simpler than rotating wing aircraft and have been studied intensely for far longer. RW designers still don’t have the tools and data to fully comprehend the complex interactional aerodynamics of RW systems. The general state of technology of onboard systems is also well behind that of modern FW aviation.
The current DoD vertical lift fleet is a “second/third generation” fleet, depending upon how you assess it, at best. It consists of core vehicle designs developed in the 1960s and 1970s that have been repeatedly upgraded over the years. Moreover, those designs were optimized for battlefield conditions that the US expected to face in a conventional war with the Soviet Union in Europe, supporting and sustaining large mechanized forces over short (tactical) distances, sustained from secure rear areas. Thirty-five years have now passed, operational demands have changed significantly, yet the aircraft designed and fielded for those Cold War conditions, notably the UH-60 Blackhawk and AH-64 Apache, remain in the force as the main-stays of the DoD fleet. Even older aircraft designs – the UH-1 Huey (Iroquois), AH-1 Cobra, CH-47 Chinook, and CH-53 Sea Stallion – were birthed and employed during the Vietnam War. The V-22 is the only new RW aircraft configuration developed since the 80’s and it’s design is rooted in the same period.
Throughout this 50-year time period, military investment has dominated the US vertical lift aircraft market. However, for the last three decades, DOD has focused vertical lift R&D investment mainly on phased block upgrades to the current fleet. As a result, innovation in RW technology has suffered, the average age of the engineering workforce has risen, the ability of industry to generate new designs has atrophied, and the US rotary wing industry is becoming less and less competitive in international markets as the years go by. While there are many reasons for the policy choices that underpin these undesirable trends, their negative effects are apparent.
The contrast with fixed wing aircraft technology innovation is stark. With fielding of the F-22 Raptor and F-35 Lightning in progress, the USAF and USN are now actively working to define the “6th generation” fighter considered necessary to maintain air dominance for introduction into the force beginning ~2030. The primary military competitors of the US – Russia and China – are still in the initial stages of fielding 5th generation. The US remains the world leader in this technology area and the Department is fully committed to retain technology overmatch.
I tried to find the historical investment levels for FW versus RW S&T to share with you but failed to find the material I was looking for. I did find an FY09 briefing from OSD DDR&E that shows that RW investment is about 14% of the total air platforms portfolio. I think that is about the level I have seen over the years. It is mildly misleading because turbine engines are accounted separately, but it is easily a 4-5 to 1 difference in the level of investment between FW and RW aircraft in the DoD.
Sub-Question: You mentioned a concern about US competitiveness in world markets. Who are the primary international competitors challenging the US today in RW technology and innovation?
Tenney: Although US foreign military sales of RW aircraft remain relatively healthy, it would be fair to say that Europe has moved ahead of the US with respect to innovation and variety. Today, European-made helicopters encompass a wide variety of commercial and military aircraft and compete aggressively against US industry. This increasingly strong position has been fueled in part by the fact that, in Jan 2001, all the major political and industry players in European aviation endorsed a 20 year vision (European Aeronautics: A Vision for 2020). The vision proposed combining public and private investment to achieve two primary goals: global leadership in the marketplace and a world class air transport system for Europe. A recent article in Aviation Week (28 Jan 14) described high hopes for the Clean Sky 2 public/private research program, which is expected to include two fast rotorcraft demonstrators, a tilt-rotor concept led by Agusta/Westland and a compound helicopter led by Airbus Helicopters (formerly Eurocopter). Clean Sky 2 is intended to run from 2014-2023, supported by $5.5B in public/industry funding. This is a huge investment and shows Europe’s collective commitment to dominating the aviation landscape. In addition, some companies like Agusta/Westland are experimenting with very aggressive developmental timelines, trying to create the processes and organization that will enable industry to move much more quickly from concept design to an actual flight article. This is a U.S. national economic challenge as well as a military one.
China lags significantly behind the West in terms of the capabilities of its fielded fleet of helicopters, but the country appears to be committed to closing that gap and moving further ahead. Like its European counterparts, Avicopter is also developing several high-speed configurations. The Jueying is a compound technology demonstrator that combines coaxial rigid rotors and nose-mounted counter-rotating propellers, with a projected speed of 270 knots. The Feihong, also in flight testing, is a VTOL, swept-wing aircraft with a piston-driven air fan mounted in the middle of the fuselage. Perhaps the boldest concept, the Blue Whale is a design with four tilt-rotors and a design payload of 44,000 lbs, max range of 1,930 miles, altitude of 28,000’, max speed of 290 knots, and combat radius of 440 nm. Blue Whale looks a lot like the Bell Helicopter Quad Tiltrotor from a few years ago. Thus far, no militarized versions of these aircraft have been revealed, although Avicopter certainly understands that support by the Chinese military will be necessary for their further development.
What are the technologies that hold the most promise for revolutionizing current systems?
Tenney: New aircraft configurations are what are required to achieve the kind of performance essential to future military operations and commercial markets. Tiltrotor aircraft, proven viable by the V-22, show great promise to make dramatic performance improvements in all realms of flight using advanced technologies. Compound helicopters, which use a combination of auxiliary propulsion and/or lift supplementation, also offer improvements in speed and efficiency. Other configurations, which were tried in the 50s and 60s, may also prove to be viable with the advent of new technologies.
The technology areas that enable these configurations are similar to what made current conventional helicopters viable and continue to improve their performance over the first generation systems of the 60s/70s. Advanced rotor systems that allow for increased speed and efficiency are first on the slate. Whether it be tilting rotors which serve as both lift and propulsive force or edgewise rotors that are slowed or designed in different ways to retain lift and control at significantly higher speeds. The rotor design and approach is a key fundamental technology that sets much of the rest of the aircraft. We need investment in the aerodynamics, dynamics, structure, and control of rotor systems. The rotor hub is included as a basic part of the rotor system and has been one of the least invested in elements over the last few decades.
The next set of technologies is those that power and drive the rotor system. Mechanical and electrical drives are heavy and expensive. These systems scale by torque and are a significant element of the aircraft empty weight. New technologies that reduce losses in these systems, reduce weight, and improve reliability pay huge dividends in both acquisition and sustainment costs. Likewise, turboshaft engines and the subsystems that generate power for the main drives and aircraft systems need constant improvement. Today’s turbine engines are much better than those of the early vintage but they have been designed to operate most efficiently in conventional helicopters at a constant speed. We know that variable speed operation, whether through the engine or drive system or a combination of both, bring significant efficiencies for future systems. We need real investment in these technologies.
VTOL systems are extremely sensitive to weight. More so than FW systems. In a FW system, you can compensate for a little more weight by longer landing and takeoff runs. There is definitely a penalty there, but not like there is in a VTOL system. In a VTOL aircraft, every added pound translates into that much more lift and installed power to get it off the ground. So everything that creates weight is a ripe area for technology contribution. The basic aircraft structure, flight control schema that control loads imparted into that structure, and all of the subsystems needed to make the aircraft functional are in need of technology contribution. Simple things that you might not think much about, such as wiring weight, are significant in our aircraft.
The threat environment is getting more challenging for all of aviation, but especially for those systems that insert, extract, and protect ground forces. New technologies to manage signatures, provide self-protection, and survive damage are vital considerations. Each such addition to the aircraft adds weight, drag, cost, and complexity and effects the overall performance of the aircraft. Lasers are a real threat for future systems and new means of protecting both humans and sensors will be a primary consideration on the next battlefield.
I could go on and on. But suffice it to say, that in order to realize new, faster, more efficient, more survivable, higher reliability, and lower footprint aircraft requires the combination of new aircraft configurations and the supporting component technologies that enable them.
“Lessons learned. Tradeoffs. Taking advantage of previous investments. The need for further study. If there’s one thing the US Army and Marine Corps share, it’s a host of well-worn phrases trotted out at congressional oversight hearings to explain why their latest attempts to build a new combat vehicle will be different from previous failures. In the midst of fighting two wars, the two services poured billions of dollars into developing, then scrapping, expensive next-generation vehicles. But they both promise the investments haven’t been wasted and that, this time, they have truly learned from the mistakes of the past.”
“On Monday, the top spokesman for General Dynamics Land Systems, Peter Keating, told me GDLS could not compete for the Armored Multi-Purpose Vehicle (APMV) program unless the Army changed how it ran the competition. Today, as even Keating expected, the Army officially denied the GDLS protest. Breaking Defense obtained a copy of the decision just an hour ago. We’ve already received statements from Army Materiel Command, General Dynamics and its rival BAE Systems, the odds-on favorite to win the contract. You can read all these documents below and click here to read our analysis of the AMPV program and why General Dynamics protested in the first place.”
“House Budget Committee Chairman Paul Ryan laid out a budget vision Tuesday that goes beyond President Obama's request by ramping up defense spending beyond the caps in 2016 and restoring them by 2017. Ryan does this by taking from the nondefense side of the ledger and still reducing overall federal spending beyond what is contemplated under the total sequester caps. "This budget rejects the president's cuts to national security.… It also keeps faith with the veterans who have served and protected the nation," declares the Ryan budget, which increases defense spending above what President Obama has called for by $273 billion over the 10-year budget window.”
“General Dynamics Land Systems cannot and will not compete for the Army’s largest surviving weapons program, the Armored Multi-Purpose Vehicle, unless the service changes how it is handling the program, GDLS’s senior spokesman told me yesterday afternoon. A GDLS withdrawal would be yet another embarrassment for the Army’s chronically troubled acquisition system, since it would effectively leave AMPV with a single bidder to replace its aging and vulnerable M113 transports, BAE Systems, which is offering a modified version of its current M2 Bradley.”
“In a world where security challenges do not adhere to political boundaries and our economies are linked as never before, no nation can go it alone and hope to prosper. Achieving sustained security and prosperity in the 21st century requires nations to work together and to meet common challenges with uncommon unity and purpose.”
In this February 21. 2014 interview, Bruce Tenney, Chief of Advance Design at Aviation and Missile Research Development and Engineering Center, discusses several technologies which could advance rotorcraft aviation. He sees advances in almost all areas of “what makes a rotorcraft a rotorcraft,” underscoring the importance of developing modern rotors and engines. Tenney also comments on the need to operate across the spectrum of altitudes and with variable speeds, and best to achieve these goals.
In this February 21. 2014 interview, Bruce Tenney, Chief of Advance Design at Aviation and Missile Research Development and Engineering Center, discusses the issues posed by the proliferation of A2/AD technologies. Tenney discusses what advanced vertical lift can mean for the Army and how increased speed and range from future rotorcraft can help overcome threats from non-state actors. He sees the depth, endurance, and speed of Vertical Take Off and Landing craft as critical to future operations.