Helicopter Launch and Recovery Methodologies – Offshore versus Navy

As a young helicopter pilot in the navy many years ago, terms like Performance Class 1, Category A operations, ‘hostile’ environment etc. were terms alien to me. Happy to jump & grab any opportunity to fly, we merrily chugged along over the sea in conditions ranging from blue skies and glassy seas to days when even birds were walking. Now with some experience, wisdom of a thousand hours of civil aviation and much jargon collected from DGCA, EASA, FAA, CASA etc, I am wondering if ignorance was truly bliss.

Civil aviation is a highly regulated sector where passenger safety is given utmost importance. Rightly so, since any accident may not only lead to needless loss of life, but also erode passenger confidence in the industry – both totally unacceptable. While flying off ships in the navy, we did what we could within the framework of ‘operational requirements’ to ensure safety. Indeed, there was a time when best practices from the military were adopted by the civil world.

Driven by the high human & material costs associated with accidents, technological advancements and regulatory requirements that get tightened with each accident or incident, civil aviation has evolved to be the safest mode of transportation. Globally, passenger numbers are expected to reach 7 billion by 2034 with a 3.8% average annual growth in demand (2014 baseline year). India is expected to become the third largest aviation market in the world by 2020.

With vast strides having been made in improving safety in civil aviation, it is perhaps useful to compare some aspects of civil aviation with the way the navy flies. Limiting the discussion to a very narrow scope of helicopter launch & recovery (L&R), a small comparison of civil versus navy methodologies reveals a few grey areas in our L&R philosophy:

  • Shore diversion is not always an option when helicopters are launched from naval ships. So in effect, you are ‘committed’ to an afloat landing the moment you rotate from hover.
  • We do not always sail in the company of an aircraft carrier or large flat-tops that can be used as a diversion for run-on landings.
  • No consideration is given to whether helicopter can undertake safe ditching in the prevalent seas. SHOL is the only criteria for launch & recovery.
  • SHOL development is still an evolving area in Indian Navy. We still do not have a dedicated setup with human, material and engineering resources to undertake scientific, data-driven SHOL tests. High-risk tasks such as afloat OEI landing can neither be simulated nor tested realistically.

Naval helicopters operate in lee of the hangar and wake of ship’s exhaust. All our decks, save for large ships such as the aircraft carrier or LPD are designed for fore & aft landing. As opposed to civil offshore operations, naval helicopters operate into the obstacle-ridden sector. All approaches are stern-on terminating in either a hover short of the deck or to one quarter, before transiting onto the deck. Deck markings and landing aids are also oriented to suit astern approaches. No SOP I ever came across in the navy caters for a ‘decision point’ where the seminal decision to continue with the landing or undertake a baulked landing (to divert to shore or set up for a planned OEI afloat landing) is taken. To our credit, there have been few odd cases where the Seaking (S-61) or Kamov-25 (Hormone) undertook successful small deck landing with one engine failed or at partial power, but even here the failure happened during other phases of flight allowing for a premeditated landing on deck. Are we ready for such a situation on short final approach? Or while initiating takeoff from deck? Ironically, these are phases where the consort (with all its fuel and ammo!) may come within the dangerous ambit of a crashed helicopter.

To cut a long story short, most, if not all, naval helicopter operations from ships (except the Carrier) are Performance Class 2 (definitions & abbreviations footnoted). Partly because of the type of helicopter and partly since take-off and landing profiles that have been adopted have not adequately dwelt on this aspect. Also, helicopters operated in Performance Class 1 are required to be certificated under Category A – a qualitative requirement slowly creeping into Indian Navy’s future helicopter staff requirements but hitherto completely missing or ignored. Presently, none of our RFMs specify profiles to be flown for Category A operations.

On the other side of the spectrum, we still operate vintage Performance Class 3 Alouettes over sea with graceless impunity. Hopefully, the NUH will come with engine and system isolation features that improve safety of operations over sea.

It would be a tall order to change flight deck design of legacy ships. For such ships and helicopters, it may perhaps be prudent to adopt L&R methodologies, including, where necessary, oblique line-up for L&R, and/or implement necessary restrictions to bring it closer to a Category A profile. NSQRs of future helicopters must cater for this requirement since some helicopters such as the future NMRH (Commando version) and Heavy Lift Helicopter (HLH) would have a substantial carrying capacity. Naval helicopters operate over ‘hostile’ environment for the most part.

Although CAT A requirements are applicable only for civil registered helicopters as of now, there is merit in adopting few of these specifications for the Service as well since it pertains to safety. All helicopters under consideration for the NMRH are derivatives of successful military / civil airframes that have met robust certification requirements, including Category A certification. Let us not lose out on some key ‘optional’ because of our short sight.

During my entire career as a naval aviator, I was either ignorant, or couldn’t care less for terms like Takeoff Decision Point (TDP), Landing Decision Point (LDP), Defined Point Before Landing (DPBL), Defined Point After Take Off (DPATO) etc. I hope future generations of naval aviators will ponder over these terminologies and link Performance Classes 1, 2 and 3 with category A and B takeoff and landing profiles. Mission accomplishment with maximum safety should be our mantra.

To sum up, the type of helicopter and takeoff landing profile that you fly decides whether you land up in the drink, or on deck, or reach safe shores in the event of losing an engine. While operating from ships this could mean an unplanned ditching, or a spectacular arrival on a small deck with one engine – both hazardous. I suppose that’s enough motivation to start an energetic discussion. The Indian Navy has lost many aircrew & helicopters to accidents at sea due to pilot error or unexplained causes and those statistics are not something to gloat about. So for anyone who feels that they have ‘been there and done that’, maybe it’s time to wake up and smell the avcat.

Here’s a 2006 snap of me landing an SH-60S on the USNS Saturn. Note the oblique landing and the clear ‘getaway’ if I chose to undertake a baulked landing at LDP. Funny part is, I never knew this when I landed 🙂

Your views are welcome!

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©KP Sanjeev Kumar, 2017. All rights reserved.

Key Definitions from DGCA CAR Section 8 Series H Part 1 dated 28 Jul 14:

Category A.   With respect to helicopters, means a multi-engine helicopter designed with engine and system isolation features capable of operations using take-off and landing data scheduled under a critical engine failure concept which assures adequate designated surface area and adequate performance capability for continued safe flight or safe rejected take-off.

Category B.   With respect to helicopters, means a single-engine or multi-engine helicopter which does not meet Category A standards. Category B helicopters have no guaranteed capability to continue safe flight in the event of an engine failure, and a forced landing is assumed.

Committal Point.   The committal point is defined as the point in the approach at which the pilot flying (PF) decides that, in the event of a power unit failure being recognized, the safest option is to continue to the deck.

Performance Class 1 Helicopter.   A helicopter with performance such that, in case of engine failure, it is able to land on the rejected take-off area or safely continue the flight to an appropriate landing area.

Performance Class 2 Helicopter.   A helicopter with performance such that, in case of engine failure, it is able to safely continue the flight, except when the failure occurs prior to a defined point after take-off or after a defined point before landing, in which cases a forced landing may be required.

Performance Class 3 Helicopter.   A helicopter with performance such that, in case of engine failure at any point in the flight profile, a forced landing must be performed.

Landing decision point (LDP).   The point used in determining landing performance from which, a power unit failure having been recognized at this point, the landing may be safely continued or a baulked landing initiated.

Take-off Decision Point (TDP).   The point used in determining take-off performance from which, a engine failure occurring at this point, either a rejected take- off may be made or a take-off safely continued.
Note.- LDP and TDP applies to performance Class I helicopters.

Defined Point After Take-Off (DPATO).   The point, within the take-off and initial climb phase, before which the helicopter’s ability to continue the flight safely, with one engine inoperative, is not assured and a forced landing may be required.

Defined Point Before Landing (DPBL).   The point, within the approach and landing phase, after which the helicopter’s ability to continue the flight safely, with one engine inoperative, is not assured and a forced landing may be required.

Note. Defined points apply to helicopters operating in performance Class 2 only.

Abbreviations:

L&R.   Launch & Recovery

SHOL.  Ship Helicopter Operating Limitations

LPD.  Landing Platform Dock

SOP. Standard Operating Procedure

RFM.  Rotorcraft Flight Manual

NUH.  Naval Utility Helicopter

NSQR.  Naval Staff Qualitative Requirements

NMRH.  Naval Multi Role Helicopter

HLH.  Heavy Lift Helicopter

AVCAT.  Military Aviation Kerosene (JP-5)

6 thoughts on “Helicopter Launch and Recovery Methodologies – Offshore versus Navy

  1. Nice one KPS …. we did develop the SHOL for the Dhruv about 2 decades ago …am surprised that others haven’t added to that knowledge!! There could be exposure time discussions too … if those concerned are listening!!
    Glad you decided to stir the hornets nest !!
    All the best ,
    Hari

    1. Thanks Sir. It’s tough enough getting basic SHOL envelopes done..I think deeper discussion is possible only if those in power have the patience and wisdom to realise that there is more to this business than meets the eye 🙂

  2. I do feel we are more professional aviators now than before. Points brought out aptly and applies well even for the hill flying we have been doing without taking much account of cat 1 etc. specially for table top helipads.
    Tried to put in Cat 1 once while planning a sortie for landing above 3.9 km and found that it was better to use a Jonga than using the heptr.
    So finally let the military flying be what it is meant to be…. Safe but mission oriented….

    1. I am happy you did the trials and came to the ‘jonga’ conclusion. That’s precisely my point..question, learn, improve…Don’t bash on regardless

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