Environmental Impact


The following White Paper outlines the significant positive reduction of aerospace carbon emissions by implementation of IQVR in the US alone: Annual CO2 emission savings of 450 million kg.


Potential Reduction in Aviation Greenhouse Gas Emissions from a New, Fog-Penetrating Cockpit Vision Technology

Kerr Avionics, LLC,June, 2016


The goal in this White Paper is to derive a plausible estimate of the potential for reducing aviation contributions to Global Warming, through use of a new technology that promises to significantly reduce flight disruptions owing to fog.  While available statistics are not designed for this particular type of analysis, we will present data – referenced to authoritative sources – that enable us to derive an estimate for the most important sector of aviation polluters: U.S. passenger air carriers.


Aviation is the seventh highest polluting entity; if aviation was a country, its total emissions would approximately equal all of the sources in Germany.  At 600 million metric tons per year, this can also be characterized as ¼ metric ton per airline passenger hour.  The aviation sector is particularly problematic in that prospective “green” solutions are not apparent: unlike many other sectors shifting to renewable power, there are few commercially scalable options for decarbonizing aircraft.  Also, a relatively large percentage of the global population has yet to use air transport, and the associated pollution level is expected to triple by 2050.

Although the conversion of aviation fuel to CO2 emissions is most commonly cited, there is also a phenomenon known as “radiative forcing” from nitrous oxides, water vapor, particle emissions, and even formation of contrails leading to enhanced cirrus cloudiness.  These constituents are estimated to provide at least a 200% multiplier effect on the actual CO2 emission levels.  Because it has a lifetime of 100 years in the upper atmosphere, CO2 pollution at high altitudes is even more damaging than near the ground.  At ground level, nitrous oxides, volatile organic compounds, CO and particulates contribute to local air quality and health concerns; NOx and volatile organics also play a role in forming ground-level ozone, a primary constituent of smog.

ATTEMPTS TO ATTACK THE PROBLEM [Refs. 1, 5, 6, 7, 8, 9, 10]

Aviation is the only transportation sector without a standard for CO2 emissions anywhere.  Prominent environmental organizations have called reducing greenhouse gas emissions in the airline industry the defining global climate change issue of 2016.  The International Civil Aviation Organization (ICAO), the UN decision-making body charged with regulating such emissions, is being urged to take bold steps to prevent aviation emissions (particularly CO2) from tripling by 2050.  There is a perceived need to cut 7.8 billion metric tons of emissions, in the period 2020-2040, in order to meet stated goals – which do not take into account anticipated future lowering of global emission-cap levels.

While Europe is preparing for inclusion of aviation in their greenhouse gas emissions trading scheme, the timeline for policy in the U.S. is less clear.  Market based measures, trading and capping, and even the enforced decreasing of airline passenger miles (which seems unlikely) are all under discussion on the international/U.N. level.  The U.S. EPA finally identified CO2 from aircraft as a health hazard in 2015, kicking off a process to regulate greenhouse gas emissions from the aviation industry; cooperative approaches with ICAO global standards efforts are now being developed.

The advent of “NextGen” technology is helping.  This includes Computer Directed Navigation and Automatic Dependent Surveillance-Broadcast (ADS-B), along with autopilots, Head-Up Displays (HUD) and Enhanced Vision Systems (EVS), all aimed at increasing flight efficiency and thereby reducing fuel use and the associated emissions.  For example, in the U.S. over 500 runways with basic Instrument Landing Systems (ILS) have had their long-standing 2400 foot minimum visibility reduced to 1800 feet for properly equipped aircraft and trained crews.

It is important to emphasize that our technology complements this thrust toward lower visibility operations, without requiring expensive equipment and infrastructure upgrades.

The numerical estimates given below are based upon domestic and international operations by U.S. air carriers (exclusive of cargo haulers).  The U.S. is by far the largest source of aviation-caused greenhouse gas emissions, and this is a segment for which some statistics can be found.  On the other hand, General Aviation, including Business Aircraft, contributes less than 1% of greenhouse gases (Ref. 3).


The effects of obscured visibility (primarily fog) include aircraft holding patterns, slowing down or circuitous routes; missed approaches/go-arounds; and diversions to alternate airports.  This gives rise to a domino effect of cascading delays throughout the system.  The anticipation of such slowdowns leads to “schedule padding” and associated higher contingency fuel loads – which reduces efficiency.  Late departures lead to higher speed flight operations and hence also reduce fuel efficiency.

When Air Traffic Control (ATC) can’t see the aircraft they are directing, they shift to a completely different set of methodologies.  Anything on the ground is literally governed by people looking out the window of the control tower.  The presence of fog dictates reliance on ILS, which uses radio signals to keep aircraft safely on the correct landing path.  Because safety standards are so high, the amount of aircraft that are processed in a given time period is dramatically decreased.  Controllers space them out, and for example do not permit one aircraft on the runway while another is executing a landing approach, because the former could interfere with ILS beacons.  Flow efficiencies are dramatically reduced, and the ripple effect is particularly strong for airports operating at near peak capacity – which is becoming more and more prevalent.


We offer a plausible rough estimate of the potential savings that can be realized with wide adoption of our fog-penetrating technology, particularly when attended by further regulatory adjustments for its capabilities.  The DOT/FAA database that we use is from Refs. 12, 13.

For U.S. Airline domestic operations in calendar year 2015:

  • Total number of operations: 5.82 M
  • On time arrival 92% of operations
  • Total delays 08% of operations

Determining weather-caused delays that are relevant to the present topic has its subtleties.  The DOT/FAA database uses the term “weather delay” in two different contexts:

  • “Extreme” weather, which by definition relates to winds, thunderstorms etc. and is not relevant here
  • All-inclusive weather delays, which in addition to the above, include “National Air System Delays” as well as “Late Arriving Aircraft”, both largely owing to visibility, which is relevant

In order to deduce the visibility-relevant delays, it is necessary to subtract “extreme-weather delays” from total weather delays.  The results for domestic airline operations in 2015 are:

  • Total weather delays 53 M minutes (averaging 62 minutes/affected operation)
  • Less extreme-weather delays 10 M minutes

RESULT                 17.43 M minutes

This is approximately 5% of the total domestic airline operational minutes for the year.  We then estimate that our technology will save 20% of these visibility-related delay minutes, or 1% of total operational minutes.  This is conservative on its own merits, and even more so in relationship to third-world countries, where they regularly fly in Instrument Flight Rule (IFR) conditions but using visual means; it will also be larger when considering rotor wing operations such as Emergency Medical Services and offshore oil rigs.  We then note that each airborne delay minute is estimated to result in the consumption of 60 lbs of fuel (Ref. 6), which corresponds to 530 gallons per hour (1 gallon = 6.8 lbs of fuel).  Finally, we note that each pound of fuel results in 1.43 kg of CO2 emissions (Ref. 2):

Annual CO2 emission savings = 20% X 17.4 M minutes X 60 lb/min X 1.43 kg/lb = 300 million kg

This is exclusive of the 2X radiative-forcing multiplier described above.  It represents 208 million pounds or 30.6 million gallons of saved fuel, and affects 56,000 flight operations.

We can scale this up to total U.S. airline operations, including international flights, by noting that there were 8.9M such operations in 2015, which is a factor of 1.5 greater than the 5.8M domestic operations.  Thus the total annual CO2 emission savings by U.S. carriers would be 450 million kg, plus a radiative-forcing multiplier of approximately 2X.

Finally, we can roughly scale this up to worldwide jet aircraft operations in all categories, using the fact that global jet fuel consumption is 3.5X that of U.S. carriers (Refs. 14,15).  If we conservatively apply this multiplier only to U.S. carrier domestic operations, we have 1.05 billion kg in CO2 emissions savings annually, again exclusive of the radiative forcing factor of 2X.  This result represents ½ percent (0.005) of the 20-year aviation emissions savings goal mentioned above (7.8 billion metric tons).


  1. http://www.worldwildlife.org/press-releases/flightpath-1-5-launches-100-days-after-cop21-to-urge-united-nations-to-cap-and-cut-aviation-s-climate-pollution
  2. carbonindependent.org
  3. https://www.nbaa.org/ops/environment/ei-executive-summary.php
  4. http://www.aef.org.uk/issues/climate/
  5. http://www.huffingtonpost.co.uk/james-lees/america-is-finally-taking_b_7552934.html
  6. http://atmseminar.org/seminarContent/seminar9/papers/72-Ryerson-Final-Paper-4-14-11.pdf
  7. https://www.faa.gov/nextgen/snapshots/stories/?slide=17
  8. http://www.flightpath1point5.org/
  9. https://uploads.strikinglycdn.com/files/8ffcdbaa-85f4-4407-bea3-fda9eedfc12f/ICSA_FAQs.pdf?id=26290
  10. http://www.theguardian.com/environment/2015/jun/10/carbon-emissions-aircraft-endanger-human-health-us-epa
  11. http://www.ibtimes.com/why-does-fog-cause-so-many-flight-delays-1929723
  12. http://www.transtats.bts.gov/OT_Delay/OT_DelayCause1.asp
  13. http://www.rita.dot.gov/bts/help/aviation/html/understanding.html
  14. http://www.indexmundi.com/energy.aspx?country=us&product=jet-fuel&graph=consumption
  15. http://www.indexmundi.com/energy.aspx?product=jet-fuel