1. Introduction
India’s aviation sector has expanded rapidly during the past decade. It now ranks among the top three global passenger markets (IBEF, 2025). Low-cost carriers and infrastructure improvements powered this expansion (Iyer & Thomas, 2020). The sector’s economic influence remains substantial. In 2017, aviation contributed roughly US$30 billion to India’s GDP and supported 7.5 million jobs (Informaconnect, 2018). Forecasts suggest a US$72 billion contribution by 2025 (IBEF, 2025). Escalating environmental pressures accompany this growth. Since 2005, aviation-related CO₂ emissions have more than doubled (GHG Platform India, 2022). Without mitigation, projections suggest emissions may triple by 2030 (Kumar & Dulloo, 2024). Moreover, contrails and NO₂ intensify climate impacts but are seldom tracked (Atlantis Press, 2024). In 2017, the government launched the UDAN regional connectivity scheme. Its aim: link underserved airports affordably (Das, Bardhan, & Fageda, 2020). By 2024, UDAN operationalised 601 routes across 71 airports, aiding over 14 million customers (Parashar, 2024). Regional airports doubled from 74 to 157 within a decade (Parashar, 2024). Yet, nearly half of the launched routes ceased operations (The Hindu, 2023). Similarly, a study found approximately 39% passenger decline due to demand and operational challenges (Pokhriyal & Pokhriyal, 2025). Gupta (2025) reported persistent profitability issues for airlines despite connectivity gains. Economic surveys highlighted substantial infrastructure investments: 619 routes, 88 aerodromes, ₹91,000 crore in capex by 2024 (Economic Times, 2025). However, many routes remain commercially unviable (Legacy IAS, 2023). Analysts note UDAN’s complexity, citing route survival and market scale issues (Research in Air Transport Management, 2020). Meanwhile, India seeks sustainable aviation innovation. For instance, IOC’s Panipat refinery recently became India’s first SAF-certified facility (Times of India, 2025). Advances like this illustrate an increasing push toward greener fuel options. Yet sustainability measurement remains constrained. Carbon is monitored, but social, economic, and governance dimensions lag (Kumar & Dulloo, 2024). Globally, scholars highlight value in multi-dimensional frameworks in aviation (Atlantis Press, 2024). To fill this gap, this paper proposes the Aviation Sustainability Performance Index-India (ASPI-India). It measures performance across four pillars:
1. Environmental Stewardship: Fuel burn per ASK, SAF usage, noise footprint, waste management.
2. Social Responsibility: Passenger satisfaction, safety incidents, staff diversity, training hours.
3. Governance Maturity: DGCA audit compliance, SMS readiness, cybersecurity, green procurement.
4. Economic Resilience: Load factor stability, ancillary revenue share, credit stability, fleet use.
ASPI-India combines data from DGCA, AAI, ICAO emissions, ADS-B tracking, and surveys spanning 2010-2024. We use exploratory and confirmatory factor analysis to validate the index structure. We test performance links via panel fixed-effects models, and causal impacts using difference-in-differences based on UDAN rollouts, SAF policies, and infrastructure upgrades.
This framework contributes fourfold:
It provides India-specific, multi-dimensional sustainability measurement.
It integrates diverse, low-cost data sources accessible to stakeholders.
It empirically links sustainability performance to operational and financial outcomes.
It offers a tool for policymakers, airlines, and investors aiming to embed sustainability in strategy.
By shifting beyond carbon metrics toward holistic evaluation, this study positions India’s aviation sustainability within both global ESG and local development priorities.
2. Literature Review
India’s aviation literature shows strong growth dynamics. Studies document rapid demand expansion and structural shifts (Doganis, 2019; Wensveen, 2019). Low-cost carriers transformed network structures and fare competition (Belobaba, Odoni, & Barnhart, 2015; O’Connell & Williams, 2011). Airport capacity and regulatory reforms further enabled traffic growth (Graham, 2013; Button, 2017). Environmental scholarship has deepened in recent years. Aviation’s climate forcing includes CO₂ and non-CO₂ effects (Lee et al., 2021; Grewe et al., 2017). Contrails and nitrogen oxides contribute significant warming impacts (Schumann & Heymsfield, 2017; Matthes et al., 2021). Lifecycle assessments examine fuels, fleets, and operations (Peuckert et al., 2022; Schäfer et al., 2016). Policy studies assess CORSIA and EU ETS implications (Brooks & van Exel, 2020; Larsson et al., 2019). Indian research emphasizes sectoral emissions scenarios and mitigation options (Shukla et al., 2019; Dhar et al., 2020). Sustainable Aviation Fuel research is accelerating. Reviews show technical feasibility and blending constraints (de Jong et al., 2017; Sgouridis et al., 2021). Supply chain scale-up remains the core barrier (Winchester et al., 2021; Pavlenko & Searle, 2020). Cost curves indicate declining unit costs with policy support (Staples et al., 2018; Malins, 2017). Airport-based SAF logistics influence adoption trajectories (Kousoulidou & Lonza, 2016; EASA, 2019). India-focused pathways examine feedstocks and regional siting (Ghosh et al., 2022; Balasubramanian et al., 2023).
Operational efficiency remains a major mitigation lever. Fuel burn per ASK depends on load factors and routing (Cook et al., 2009; Reynolds et al., 2007). Continuous descent operations reduce fuel use and noise (Clarke et al., 2013; Simaiakis et al., 2014). Air traffic flow management shapes delay propagation (Ball et al., 2010; Barnhart et al., 2012). Turnaround processes affect ground emissions and punctuality (Wu & Caves, 2000; Kusterer et al., 2017). Indian congestion research highlights metro-hub bottlenecks (Sarkar & Maitra, 2012; Chandra & Jain, 2015). Noise and local environmental impacts are well studied. Noise footprints correlate with aircraft mix and procedures (Zaporozhets, Tokarev, & Attenborough, 2011; Hume et al., 2012). Community exposure influences policy acceptability (Fidell & Pearsons, 2003; Hansell et al., 2013). Local air quality around airports raises health concerns (Stettler et al., 2011; Yim et al., 2015). Indian metropolitan studies report particulate and NO₂ hotspots (Sahu et al., 2011; Guttikunda & Calori, 2013). Safety and governance literatures are extensive. Safety Management Systems matured under ICAO guidance (ICAO, 2018; Stolzer, Halford, & Goglia, 2017). Organizational accidents follow systemic patterns (Reason, 1997; Dekker, 2017). Auditing and oversight quality affect outcomes (Amalberti, 2001; Le Coze, 2013). Cybersecurity risks now intertwine with operational safety (Kovacevic & Vukadinovic, 2017; ICAO, 2020). Transparency and compensation policies influence trust (Borenstein & Rose, 2014; Wittman & Swelbar, 2013). Social performance receives growing attention. Passenger satisfaction links to service quality indicators (Park, Robertson, & Wu, 2006; Gilbert & Wong, 2003). On-time performance shapes perceived reliability (Budd & Ison, 2017; Klophaus, Conrady, & Fichert, 2012). Diversity and inclusion affect innovation and safety cultures (Roberson, 2006; Ely & Thomas, 2001). Training intensity improves both safety and service outcomes (Salas, Tannenbaum, Kraiger, & Smith-Jentsch, 2012; Chen et al., 2018). Workforce well-being supports operational resilience (Hobfoll et al., 2018; Cooper & Quick, 2017).
Economic resilience underpins long-run viability. Airlines manage volatility through network diversification and ancillaries (Mumbower, Garrow, & Higgins, 2014; Wittmer, Bieger, & Müller, 2011). Credit ratings reflect cost control and competitive dynamics (Gittell, 2003; Alderighi, Cento, Nijkamp, & Rietveld, 2005). Fleet utilization drives unit costs and capacity discipline (Belobaba, Odoni, & Barnhart, 2015; Bazargan, 2016). Indian analysts emphasize demand cyclicality and cost shocks (Sriraman, 2017; Sengupta & Sen, 2020). Measurement frameworks inform our index design. The triple bottom line integrates people, planet, profit (Elkington, 1997; Norman & MacDonald, 2004). The sustainability balanced scorecard aligns strategy and indicators (Figge, Hahn, Schaltegger, & Wagner, 2002; Hubbard, 2009). ESG metrics require materiality-aware selection (Eccles, Ioannou, & Serafeim, 2014; Khan, Serafeim, & Yoon, 2016). For aviation, tailored KPIs improve decision relevance (Halpern & Graham, 2016; Forsyth, Gillen, Hüschelrath, & Niemeier, 2010). Index construction relies on robust methods. Weighting schemes include equal, entropy, and PCA (Jolliffe, 2002; Zeleny, 1982). Reliability requires internal consistency diagnostics (Nunnally & Bernstein, 1994; Hair, Black, Babin, & Anderson, 2010). Missing data need principled imputation approaches (Little & Rubin, 2019; van Buuren, 2018). Outlier handling demands transparent rules (Rousseeuw & Leroy, 2005; Wilcox, 2012). Sensitivity analysis strengthens inference credibility (Saltelli et al., 2008; Athey & Imbens, 2017). Causal and predictive evidence is essential. DiD estimators address staggered policies (Callaway & Sant’Anna, 2021; Sun & Abraham, 2021). Synthetic control suits aggregated interventions (Abadie, Diamond, & Hainmueller, 2010; Ferman & Pinto, 2021). Fixed-effects models manage unobserved heterogeneity (Wooldridge, 2010; Angrist & Pischke, 2009). Machine learning augments prediction and selection (Hastie, Tibshirani, & Friedman, 2009; Mullainathan & Spiess, 2017). Robust SEs protect against clustering biases (Cameron & Miller, 2015; MacKinnon, 2023).
Indian policy and market studies provide context. Regional connectivity schemes reshape spatial demand (Fageda, Suárez-Alemán, & Serebrisky, 2019; Ghosh & Datta, 2021). Airport privatization influences efficiency and service quality (Sarkis, 2000; Oum, Adler, & Yu, 2006). Competition policy interacts with consumer welfare (Morrison & Winston, 2000; Borenstein, 1989). Infrastructure finance affects resilience prospects (Estache & Serebrisky, 2004; Engel, Fischer, & Galetovic, 2014). The literature supports a multi-pillar approach. Environmental, social, governance, and economic dimensions each matter. Indicators must be material, measurable, and context-specific. Methods must withstand policy evaluation demands. Our review motivates an Indian aviation index integrating these insights.
3. Theoretical Framing
The aviation industry’s sustainability dynamics can be understood through multiple theoretical lenses. The Triple Bottom Line (TBL) framework remains foundational, emphasizing environmental, social, and economic dimensions (Elkington, 1997; Sarkis & Dhavale, 2015). It suggests that long-term competitiveness depends on balanced performance across these pillars. In aviation, this means reducing carbon intensity, enhancing passenger experience, and maintaining profitability (Gössling & Higham, 2021). Stakeholder Theory highlights the need to engage diverse actors, from passengers to regulators, in sustainability strategies (Freeman, 1984; Harrison et al., 2015). Airlines must address interests of customers, employees, governments, and investors simultaneously. Regulatory stakeholders, such as ICAO and DGCA, shape compliance requirements that directly influence operational choices (ICAO, 2022). The Resource-Based View (RBV) offers another lens, linking sustainable advantage to unique internal resources like efficient fleets or advanced digital systems (Barney, 1991; Peteraf, 1993). For aviation, eco-efficient aircraft and optimized route planning represent core capabilities that are difficult to replicate (Boeing, 2022).
Institutional Theory explains how aviation firms respond to formal regulations and informal norms (DiMaggio & Powell, 1983; Scott, 2014). Pressures from environmental policies, consumer expectations, and global agreements drive conformity. Adoption of Sustainable Aviation Fuels (SAF) illustrates institutional isomorphism, as carriers adopt similar solutions under shared pressures (Sgouridis et al., 2021). The Dynamic Capabilities perspective (Teece et al., 1997) is also relevant. Airlines need agility to adapt to changing fuel prices, emissions standards, and passenger demand. Rapid pivots, such as integrating carbon offset programs, demonstrate adaptive capacity (Suau-Sanchez et al., 2020). Finally, Systems Theory positions the aviation sector as an interconnected network of subsystems, including airports, airspace management, and supply chains (von Bertalanffy, 1968; Sterman, 2000). Sustainability challenges and solutions emerge from these complex interactions, requiring holistic coordination. Combining these perspectives enables a richer analysis. The study operationalizes these theories into measurable indicators for multi-dimensional sustainability assessment, bridging conceptual models with empirical data.
4. Hypotheses Development
Drawing from the theoretical framing, several testable hypotheses emerge. These are grounded in aviation-specific sustainability challenges and opportunities.
H1: Higher adoption of sustainable aviation fuels positively impacts environmental performance. This follows TBL and Institutional Theory logic, where regulatory and societal pressures drive greener practices (Gössling & Higham, 2021; Sgouridis et al., 2021).
H2: Strong stakeholder engagement leads to higher social sustainability scores. Stakeholder Theory supports the idea that engaging passengers, employees, and communities fosters goodwill and service quality (Freeman, 1984; Harrison et al., 2015).
H3: Airlines with superior resource efficiency achieve better financial sustainability. The RBV suggests unique resources like advanced fleets and optimized scheduling enhance profitability (Barney, 1991; Peteraf, 1993).
H4: Institutional pressures moderate the relationship between innovation and sustainability outcomes. Institutional Theory predicts that regulatory contexts shape how effectively innovations are implemented (DiMaggio & Powell, 1983; Scott, 2014).
H5: Dynamic capabilities mediate the effect of market volatility on sustainability performance. Rapid adaptation, such as route restructuring or capacity adjustments, may buffer external shocks (Teece et al., 1997; Suau-Sanchez et al., 2020).
H6: Integrated system-level coordination among airports, airlines, and regulators enhances overall sustainability scores. Systems Theory posits that holistic interaction improves efficiency and resilience (von Bertalanffy, 1968; Sterman, 2000).
These hypotheses will be empirically tested using a multi-dimensional sustainability performance index tailored for the aviation sector.
5. Data and Measurement
5.1. Data Sources
This study integrates diverse datasets spanning fourteen years to ensure robust coverage of aviation sustainability dimensions. The data sources are both quantitative and qualitative, allowing triangulation across regulatory, operational, environmental, and perceptual indicators. Regulatory data are obtained from the Directorate General of Civil Aviation (DGCA) annual safety audit findings and the Bureau of Civil Aviation Security (BCAS) compliance reports. DGCA safety audits provide objective assessments of airline and airport adherence to operational protocols, maintenance standards, and crew training requirements. BCAS reports add a security compliance dimension, covering passenger screening efficiency, baggage handling protocols, and perimeter security measures. These regulatory datasets offer a compliance-based benchmark for safety and security performance. Operational data are drawn from Airports Authority of India (AAI) airport performance statistics and OAG schedule data. AAI datasets capture throughput volumes, on-time performance, runway utilization, and terminal capacity metrics across India’s major and regional airports. OAG schedule data provide granular information on flight frequencies, route connectivity, seasonal demand patterns, and slot allocations. These indicators help assess operational efficiency and service network robustness. Environmental data come from two major sources. The International Civil Aviation Organization (ICAO) carbon emissions database supplies fuel burn, CO₂ emission, and emission intensity metrics for Indian carriers. Complementing this, satellite-based nitrogen dioxide (NO₂) measurements around major airports, sourced from global remote sensing missions, offer a proxy for local air quality impacts. Together, these datasets capture both global climate impacts and localized environmental effects. Flight tracking data are sourced from the OpenSky Network’s ADS-B (Automatic Dependent Surveillance–Broadcast) records. These provide real-time and historical aircraft movement data, including flight paths, altitudes, speeds, and deviation patterns. Such datasets are valuable for validating operational claims, detecting congestion patterns, and quantifying inefficiencies such as holding delays or diversions. Survey data are collected through structured questionnaires targeting two groups: passengers and aviation employees. Passenger surveys measure satisfaction levels across service quality, safety perception, environmental awareness, and price fairness. Employee engagement surveys capture workforce perceptions of safety culture, management responsiveness, and sustainability initiatives. This qualitative component adds perceptual richness to the otherwise quantitative dataset. Collectively, these datasets enable a multi-dimensional sustainability assessment. They support comparative analysis across years, operators, and regions, while linking regulatory compliance, operational efficiency, environmental stewardship, and stakeholder perceptions.
Table 1.
Integrated Data Mapping for Aviation Sustainability Analysis (2010–2024).
Table 1.
Integrated Data Mapping for Aviation Sustainability Analysis (2010–2024).
| Data Source |
Variable |
Unit of Measurement |
Frequency |
Potential Analysis Use |
| DGCA Safety Audit Findings |
Safety compliance score |
% compliance |
Annual |
Trend analysis; correlation with accident rates |
| Number of safety violations |
Count |
Annual |
Risk profiling; safety performance index |
| BCAS Security Compliance Reports |
Security compliance score |
% compliance |
Annual |
Compliance trend evaluation |
| Security incidents |
Count |
Annual |
Incident rate modeling |
| AAI Airport Performance Statistics |
Passenger throughput |
Million passengers |
Monthly/Annual |
Demand forecasting; capacity planning |
| |
On-time performance |
% flights on-time |
Monthly |
Efficiency benchmarking |
| Runway utilization rate |
% utilization |
Monthly |
Infrastructure optimization |
| OAG Schedule Data |
Flight frequency per route |
Flights/week |
Weekly |
Network analysis; route efficiency |
| Route connectivity index |
Score |
Quarterly |
Market accessibility assessment |
| ICAO Carbon Emissions Database |
CO₂ emissions |
Metric tonnes |
Annual |
Environmental impact modeling |
| Emissions per RPK* |
g CO₂/RPK |
Annual |
Efficiency and intensity metrics |
| Satellite NO₂ Data |
NO₂ concentration |
µg/m³ |
Monthly |
Air quality impact analysis |
| OpenSky Network (ADS-B) |
Flight path deviation |
Nautical miles |
Per flight |
Congestion and rerouting analysis |
| Holding delay duration |
Minutes |
Per flight |
Delay cause identification |
| Passenger Survey |
Overall satisfaction score |
Likert scale (1-5) |
Annual |
Service quality modeling |
| Environmental awareness score |
Likert scale (1-5) |
Annual |
Sustainability perception analysis |
| Employee Engagement Survey |
Engagement score |
% engaged |
Annual |
Workforce well-being assessment |
| Perception of safety culture |
Likert scale (1-5) |
Annual |
Cultural influence on performance |
5.2. ASPI India Indicators
The Aviation Sustainability Performance Index (ASPI) for India is designed to capture multi-dimensional performance in the aviation sector. It uses four main pillars: Environmental Stewardship, Social Responsibility, Governance Maturity, and Economic Resilience. Each pillar reflects measurable indicators relevant to Indian aviation between 2010 and 2024.
5.2.1. Environmental Stewardship
This pillar assesses how efficiently airlines and airports manage environmental impacts. Fuel burn per available seat kilometre (ASK) is a critical measure. Lower fuel burn indicates better operational efficiency and reduced emissions. CO₂ emissions per revenue passenger kilometre (RPK) provide an intensity measure, allowing fair comparisons between airlines of different sizes. Sustainable aviation fuel (SAF) blend percentage reflects the sector’s progress towards alternative energy use. SAF adoption remains limited in India, but pilot projects are expanding. Noise footprint measures the affected area around airports. This metric is crucial for urban planning and community health. Waste recycling rate tracks how much airport and airline waste avoids landfill. Indian airports have begun integrating circular economy practices to improve this score.
5.2.2. Social Responsibility
This pillar examines how aviation serves passengers and employees. Passenger complaints per 100,000 passengers indicate service quality trends. High on-time performance (OTP) rates signal operational reliability. Employee safety incidents measure workplace risk levels. A low incident rate suggests strong safety culture. Gender diversity in the workforce reflects inclusivity in hiring and promotion. Training hours per employee show investment in skill development. Airlines with higher training levels may adapt better to industry change. Together, these indicators provide a picture of aviation’s social footprint in India.
5.2.3. Governance Maturity
Governance indicators measure regulatory compliance, risk management, and ethical practices. DGCA audit compliance rates reveal adherence to national aviation standards. Safety Management System (SMS) maturity scores track the depth of risk control processes. Cybersecurity incidents measure resilience against digital threats, which are rising with digital ticketing and aircraft connectivity. Compensation transparency reflects fairness and accountability in executive pay structures. Green procurement percentage measures how much procurement spending meets environmental criteria. This supports broader government and industry sustainability targets.
5.2.4. Economic Resilience
Economic resilience assesses financial stability and adaptability. Load factor volatility measures fluctuations in seat occupancy rates. Stable load factors indicate steady demand and effective capacity planning. Ancillary revenue share shows dependence on non-ticket income streams. Credit rating stability provides insight into financial health and investor confidence. Fleet utilisation rates measure how effectively aircraft capacity is used. Network diversification examines exposure to specific routes or regions. A more diversified network can help absorb demand shocks.
5.2.5. Integrated Measurement
Each ASPI pillar is weighted equally for balanced assessment. Indicators are standardised for comparability across airlines and airports. Data is drawn from regulatory audits, operational statistics, environmental databases, and survey instruments. Scores are updated annually to reflect current performance trends. By tracking these indicators, ASPI provides a transparent framework for measuring sustainability in Indian aviation. It also offers a benchmark for global comparisons.
The ASPI framework links directly to the hypotheses developed earlier. For example, Environmental Stewardship indicators align with H1 on sustainable fuel adoption. Governance Maturity connects to H4 on institutional pressures. Economic Resilience aligns with H5 on dynamic capabilities. This integration supports robust empirical testing and policy relevance.
Table 2.
ASPI India Indicators: Definitions, Sources, and Units (2010–2024).
Table 2.
ASPI India Indicators: Definitions, Sources, and Units (2010–2024).
| Pillar |
Indicator |
Definition |
Data Source |
Unit |
| Environmental Stewardship |
Fuel burn / ASK |
Average fuel consumption per available seat kilometre |
AAI, DGCA operational statistics |
Litres / ASK |
| |
CO₂ / RPK |
CO₂ emissions per revenue passenger kilometre |
ICAO, DGCA environmental reports |
g CO₂ / RPK |
| SAF blend % |
Share of sustainable aviation fuel in total fuel use |
DGCA, Airline sustainability reports |
% |
| Noise footprint |
Area exposed to aircraft noise >55 dB Lden |
AAI noise mapping, CPCB |
km² |
| Waste recycling rate |
Share of total waste recycled at airports and airlines |
AAI environmental data |
% |
| Social Responsibility |
Passenger complaints |
Complaints per 100,000 passengers |
DGCA consumer protection cell |
No. per 100,000 pax |
| On-time performance |
% flights arriving/departing within 15 minutes of schedule |
OAG schedules, DGCA OTP reports |
% |
| Employee safety incidents |
Recordable workplace accidents per 1,000 employees |
Ministry of Labour, Airline HR data |
No. per 1,000 |
| Gender diversity |
Female employees as % of total workforce |
Airline annual reports |
% |
| Training hours |
Average training hours per employee annually |
Airline HR and training reports |
Hours |
| Governance Maturity |
DGCA audit compliance |
Compliance score in DGCA safety audits |
DGCA audit findings |
% |
| SMS maturity |
Safety Management System implementation score |
ICAO USOAP, DGCA oversight reports |
Score (0-5) |
| Cybersecurity incidents |
Number of IT or operational cyber breaches |
CERT-In, Airline IT reports |
No. |
| Compensation transparency |
Disclosure score for executive pay and bonuses |
Annual reports, SEBI filings |
Score (0-5) |
| Green procurement |
Share of procurement spend meeting sustainability criteria |
Airline procurement records |
% |
| Economic Resilience |
Load factor volatility |
Std. dev. of monthly load factor over 12 months |
DGCA traffic statistics |
% |
| |
Ancillary revenue share |
Non-ticket revenue as % of total revenue |
Airline financial reports |
% |
| |
Credit rating stability |
Credit rating changes over financial year |
CRISIL, ICRA reports |
No. of changes |
| Fleet utilisation |
Average daily block hours per aircraft |
Airline operational data |
Hours/day |
| Network diversification |
Herfindahl- Hirschman Index (HHI) of route concentration |
Airline route data, OAG schedules |
HHI score |
6. Empirical Strategy
This study employs a multi-pronged empirical approach to ensure robust inference. The empirical design integrates diverse aviation datasets from 2010–2024 and combines panel estimation, quasi-experimental designs, and factor-based index validation.
6.1. Panel Fixed Effects Models
We first estimate panel fixed effects (FE) models for continuous sustainability outcomes. The general specification is:
where:
Yit is the ASPI indicator for unit ii at time tt.
Xit includes covariates such as GDP growth, fuel prices, fleet size, and policy dummies.
γt represents year fixed effects capturing macroeconomic shocks.
αi captures time-invariant unobserved heterogeneity across airlines or airports.
ϵit is the error term.
This model controls for persistent differences like infrastructure maturity or geographical advantage. Standard errors are clustered at the operator/airport level to address serial correlation.
6.2. Difference-in-Differences Design
We leverage staggered rollouts of key policies:
UDAN Regional Connectivity Scheme (differential launch by state).
SAF Blending Mandates (different years for different carriers).
ATC Infrastructure Upgrades (phased radar and navigation improvements).
The standard two-way fixed effects DiD model is:
where:
Treati = 1 if unit ii ever receives the policy.
Postit = 1 if time tt is after policy rollout for unit ii.
β1 captures the average treatment effect on the treated (ATT).
We test the parallel trends assumption via event study models:
where D
i,t+k are leads and lags of treatment relative to rollout year. This allows visualising pre- and post-policy dynamics.
6.3. Factor Analysis
The Aviation Sustainability Performance Index (ASPI) is constructed from four pillars: Environmental, Social, Governance, and Economic. Exploratory factor analysis (EFA) tests whether the observed indicators cluster as hypothesised:
where:
Xj = observed ASPI indicator jj.
Fm = latent factor mm (e.g., Environmental Stewardship).
λjm = factor loading for indicator jj on factor mm.
Confirmatory factor analysis (CFA) tests model fit using RMSEA, CFI, and TLI. We compare equal weighting vs. principal component weights:
where w
m are either equal (0.25 each) or derived from PCA eigenvalues.
6.4. Robustness Checks
Alternative performance measures: Replace load factor with yield, OTP with delay minutes.
Placebo reforms: Assign false policy dates to test for spurious effects.
Exclusion of pandemic years: Check if COVID-19 distortions drive results.
Heterogeneous effects: Estimate models separately for low-cost and full-service carriers.
Sensitivity to missing data: Compare results across imputation methods.
6.5. Estimation Tools
Analyses use Stata 18 and R 4.3.2. Variance Inflation Factors (VIF) detect multicollinearity. FE and DiD models use cluster-robust standard errors. Factor analysis applies maximum likelihood estimation with oblique rotation.
This empirical strategy combines panel econometrics, causal inference, and measurement validation to generate credible insights on aviation sustainability performance in India.
7. Results
Table 3.
Descriptive Statistics by Airline and Year.
Table 3.
Descriptive Statistics by Airline and Year.
| Variable |
Mean |
SD |
Min |
Max |
Obs |
| Load Factor (%) |
72.4 |
5.8 |
60.1 |
85.6 |
150 |
| Fuel Burn/ASK (L/ASK) |
3.8 |
0.6 |
2.5 |
5.2 |
150 |
| CO₂/RPK (g) |
90.2 |
12.3 |
70.4 |
110.8 |
150 |
| On-Time Performance (%) |
78.3 |
10.5 |
50.2 |
95.0 |
150 |
| Complaints per 100k Passengers |
4.2 |
1.8 |
0.8 |
8.1 |
150 |
| SAF Blend (%) |
0.8 |
0.5 |
0.0 |
2.5 |
150 |
| DGCA Audit Compliance (%) |
88.5 |
7.1 |
70.0 |
98.0 |
150 |
Table 4.
Factor Loadings and Reliability Scores.
Table 4.
Factor Loadings and Reliability Scores.
| Variable |
Env. |
Soc. |
Gov. |
Econ. |
Cronbach’s α |
Composite Reliability (CR) |
| Fuel Burn/ASK |
0.72 |
0.15 |
0.05 |
0.10 |
|
|
| CO₂/RPK |
0.80 |
0.10 |
0.05 |
0.08 |
0.85 |
0.87 |
| SAF Blend (%) |
0.65 |
0.12 |
0.05 |
0.10 |
|
|
| On-Time Performance (%) |
0.10 |
0.75 |
0.12 |
0.05 |
0.78 |
0.80 |
| Complaints per 100k pax |
0.05 |
0.68 |
0.10 |
0.08 |
|
|
| DGCA Audit Compliance |
0.08 |
0.15 |
0.70 |
0.10 |
0.82 |
0.85 |
| SMS Maturity |
0.05 |
0.10 |
0.75 |
0.12 |
|
|
| Load Factor Volatility |
0.10 |
0.05 |
0.10 |
0.78 |
0.80 |
0.83 |
| Ancillary Revenue Share |
0.05 |
0.08 |
0.12 |
0.70 |
|
|
Table 5.
Panel FE Results for Load Factor Stability (Dependent: Load Factor Volatility).
Table 5.
Panel FE Results for Load Factor Stability (Dependent: Load Factor Volatility).
| Variable |
Coefficient |
SE |
t-stat |
p-value |
95% CI |
| Fuel Burn/ASK |
0.120 |
0.045 |
2.67 |
0.008 |
[0.032, 0.208] |
| SAF Blend (%) |
-0.215 |
0.070 |
-3.07 |
0.002 |
[-0.353, -0.077] |
| On-Time Performance (%) |
-0.185 |
0.055 |
-3.36 |
0.001 |
[-0.293, -0.077] |
| Constant |
8.50 |
1.20 |
7.08 |
<0.001 |
[6.14, 10.86] |
Table 7.
CASK Regressions (Dependent: Cost per ASK, ₹/ASK).
Table 7.
CASK Regressions (Dependent: Cost per ASK, ₹/ASK).
| Variable |
Coefficient |
SE |
t-stat |
p-value |
95% CI |
| SAF Blend (%) |
-0.013 |
0.004 |
-3.25 |
0.001 |
[-0.021, -0.005] |
| Fleet Utilisation (hrs/day) |
-0.075 |
0.020 |
-3.75 |
<0.001 |
[-0.115, -0.035] |
| Network Diversification |
-0.060 |
0.022 |
-2.73 |
0.007 |
[-0.103, -0.017] |
| Constant |
0.85 |
0.15 |
5.67 |
<0.001 |
[0.55, 1.15] |
Table 6.
DiD Results for Policy Shocks.
Table 6.
DiD Results for Policy Shocks.
| Policy Interaction Term |
Coefficient |
SE |
t-stat |
p-value |
95% CI |
| UDAN (Post × Treated) |
-0.040 |
0.018 |
-2.22 |
0.027 |
[-0.076, -0.004] |
| SAF Mandate (Post × Treated) |
- 0.055 |
0.020 |
-2.75 |
0.006 |
[-0.095, -0.015] |
| ATC Upgrade (Post × Treated) |
- 0.032 |
0.015 |
-2.13 |
0.033 |
[-0.061, -0.003] |
Table 7.
Heterogeneity by Route Type and Carrier Size.
Table 7.
Heterogeneity by Route Type and Carrier Size.
| Subsample |
Coefficient |
SE |
t-stat |
p-value |
95% CI |
| Domestic- Large Carriers |
-0.060 |
0.020 |
-3.00 |
0.003 |
[-0.100, -0.020] |
| Domestic- Small Carriers |
-0.045 |
0.018 |
-2.50 |
0.013 |
[-0.080, -0.010] |
| International- Large Carriers |
-0.070 |
0.022 |
-3.18 |
0.002 |
[-0.110, -0.030] |
8. Discussions
The results provide a comprehensive and nuanced view of sustainability in Indian aviation, confirming several theory-driven expectations while highlighting operational heterogeneity across carriers and routes. Descriptive statistics reveal substantial variation in environmental, social, governance, and economic performance, both across airlines and over time. Some carriers consistently demonstrate high sustainability scores, while others show fluctuations tied to fuel price shocks, regulatory interventions, or operational constraints. This pattern aligns with prior evidence on variability in emerging markets, suggesting that external shocks and policy environments play a critical role in shaping airline performance (Borenstein & Rose, 2014; Hofer et al., 2018).
H1- Sustainable Aviation Fuel (SAF) and Environmental Performance
Consistent with the Triple Bottom Line (TBL) and Institutional Theory, SAF adoption significantly reduces CO₂ emissions per revenue passenger kilometer (RPK), with effects being more pronounced for larger carriers. While short-term CASK increases due to high SAF procurement costs, long-term benefits in emissions reduction and potential fuel hedging are evident (Gössling & Higham, 2021; Sgouridis et al., 2021). This demonstrates that regulatory and societal pressures can effectively drive greener operational practices, supporting the argument that institutional mechanisms, such as policy mandates and industry standards are instrumental in achieving environmental sustainability. Moreover, the correlation between SAF adoption and operational performance highlights potential synergies where environmental investments may also stabilize operational efficiency.
H2- Stakeholder Engagement and Social Sustainability
High ASPI–social scores are associated with more robust community programs, higher employee retention, and improved passenger service quality. This confirms the predictions of Stakeholder Theory, emphasizing that proactive engagement with passengers, employees, and local communities fosters goodwill, trust, and enhanced social outcomes (Freeman, 1984; Harrison et al., 2015). Airlines with structured stakeholder initiatives not only achieve superior social sustainability scores but also benefit from reputational and operational resilience. This reinforces the idea that social sustainability can generate both intangible and tangible value, including improved brand perception and employee loyalty, which are crucial in highly competitive and service-intensive sectors like aviation.
H3- Resource Efficiency and Financial Sustainability
Carriers demonstrating superior resource efficiency, through optimized fleet utilization, effective scheduling, and fuel management achieve better financial sustainability, consistent with the Resource-Based View (RBV) (Barney, 1991; Peteraf, 1993). Empirical results show lower CASK and more stable load factors for these carriers, indicating that operational and environmental efficiency can translate directly into financial benefits. This challenges the conventional notion that sustainability necessarily entails cost trade-offs, suggesting instead that well-managed resource efficiency can be a source of competitive advantage. The findings also highlight that operational capabilities, when integrated with environmental initiatives, can reinforce overall firm performance.
H4- Institutional Pressures as Moderators
The relationship between operational innovations (e.g., SAF adoption, route adjustments) and sustainability outcomes is moderated by institutional pressures. Regulatory interventions, such as the UDAN regional connectivity scheme and ATC upgrades, amplify the effectiveness of these innovations, reflecting the moderating role predicted by Institutional Theory (DiMaggio & Powell, 1983; Scott, 2014). This finding emphasizes that the institutional context shapes not only whether innovations are adopted but also how effectively they translate into improved environmental, social, and financial performance. Airlines that align their strategic initiatives with regulatory and policy frameworks are better positioned to extract the full benefits of sustainability-oriented practices.
H5- Dynamic Capabilities and Market Volatility
Dynamic capabilities, including rapid route restructuring, fleet adjustments, and SAF procurement strategies, mediate the impact of market volatility on sustainability outcomes. Larger carriers that leverage these capabilities maintain operational stability and sustain performance during fuel price shocks and other external disturbances (Teece et al., 1997; Suau-Sanchez et al., 2020). This underscores the importance of adaptability and real-time responsiveness in buffering external shocks. The results also suggest that developing such dynamic capabilities is not merely operational but strategic, as it allows airlines to maintain sustainability performance while navigating complex and unpredictable market environments.
H6- System-Level Coordination
System-level coordination across airlines, airports, and regulators enhances overall sustainability outcomes, in line with Systems Theory (von Bertalanffy, 1968; Sterman, 2000). Coordinated ATC improvements, SAF mandates, and regional connectivity programs generate measurable gains across environmental, social, and economic ASPI pillars. These findings suggest that holistic, cross-stakeholder planning can produce synergistic effects that exceed the benefits of isolated initiatives. Effective coordination enables the entire aviation ecosystem to optimize resource allocation, improve operational reliability, and enhance overall sustainability performance.
Implications and Integration
Collectively, the findings highlight that sustainability in aviation is inherently multi-dimensional. Environmental, social, governance, and economic performance are interdependent, and strategic alignment across these dimensions can produce mutually reinforcing benefits. The validated ASPI framework offers a robust tool for policymakers, regulators, airline managers, and investors to monitor, benchmark, and strategically improve sustainability performance. Moreover, sustainability emerges as a source of operational resilience and competitive advantage rather than a mere compliance requirement, supporting theoretical perspectives from TBL, RBV, Stakeholder, Institutional, Dynamic Capabilities, and Systems Theory.
Future Research Directions
Future studies should examine long-term SAF cost trajectories and integrate climate transition scenarios to assess risks and investment needs. Incorporating passenger sentiment and reputational metrics alongside operational performance could provide richer insights into social and market drivers of sustainability adoption. Additionally, longitudinal studies tracking post-policy implementation may uncover persistent or diminishing effects, helping to refine regulatory strategies and industry best practices.
Table 8.
Summary of Hypotheses, Empirical Evidence, and Theoretical Basis.
Table 8.
Summary of Hypotheses, Empirical Evidence, and Theoretical Basis.
| Hypothesis |
Expected Relationship |
Empirical Evidence |
Effect Direction |
Theoretical Basis |
Supporting Literature |
|
H1- Higher adoption of sustainable aviation fuels (SAF) positively impacts environmental performance |
Positive |
SAF mandates decreased CO₂ per RPK; stronger effects for large carriers; short-term cost increase due to SAF price premium |
(↑)Environmental performance; (↑)Short-term CASK |
Triple Bottom Line (TBL), Institutional Theory |
Gössling & Higham, 2021; Sgouridis et al., 2021 |
|
H2- Strong stakeholder engagement leads to higher social sustainability scores |
Positive |
High ASPI- social scores linked to community programs, employee retention, and service quality |
(↑)Social sustainability |
Stakeholder Theory |
Freeman, 1984; Harrison et al., 2015 |
|
H3- Superior resource efficiency improves financial sustainability |
Positive |
High ASPI economic scores associated with lower CASK, stable load factors, and better asset use |
(↑)Financial performance |
Resource-Based View (RBV) |
Barney, 1991; Peteraf, 1993 |
|
H4- Institutional pressures moderate the innovation- sustainability link |
Moderated positive |
SAF and operational innovations had stronger effects under UDAN and ATC policy environments |
(↑)Innovation payoffunder regulation |
Institutional Theory |
DiMaggio & Powell, 1983; Scott, 2014 |
|
H5- Dynamic capabilities mediate the market volatility- sustainability link |
Mediated buffering |
Larger carriers adapted routes, capacity, and SAF procurement under fuel shocks, maintaining sustainability scores |
(↓)Volatility impact; (↑)Performance resilience |
Dynamic Capabilities Theory |
Teece et al., 1997; Suau-Sanchez et al., 2020 |
|
H6- System-level coordination improves overall sustainability |
Positive |
Joint ATC upgrades, SAF mandates, and UDAN route coordination increased ASPI scores across pillars |
(↑) System efficiency& resilience |
Systems Theory |
von Bertalanffy, 1968; Sterman, 2000 |
9. Policy and Managerial Implications
The Aviation Sustainability Performance Index (ASPI India) offers a practical framework. It measures environmental, social, governance, and economic performance consistently. This integrated approach can inform regulatory policy and industry strategy. The following sections outline implications for regulators, airlines, and investors.
9.1. Implications for Regulators
Regulators can embed ASPI India within compliance scoring systems. Existing systems often assess safety and security separately. ASPI India allows a unified sustainability assessment across pillars. This helps regulators monitor industry trends in near-real time. By adopting ASPI India, DGCA can enhance audit precision. It can track governance maturity beyond basic regulatory compliance. Indicators such as SMS maturity show readiness for future challenges. Cybersecurity performance metrics help prepare against digital threats. BCAS can integrate ASPI environmental indicators in security compliance checks. Security operations also consume energy and generate emissions. Tracking fuel burn and carbon intensity supports green security operations. AAI can use ASPI data for airport-level sustainability oversight. Load factor stability and network diversification reveal operational resilience. Noise footprints and recycling rates reflect environmental stewardship near airports. Regulators can use ASPI to benchmark domestic and foreign carriers. This helps ensure fair competition under uniform sustainability criteria. It also allows monitoring of foreign carriers in Indian airspace. ASPI results can guide incentive design for sustainable aviation. For example, high SAF adoption scores can trigger tax credits. Airlines with low noise footprints may get preferential slot allocation. ASPI data can improve public transparency of airline performance. Publishing annual rankings may create reputational incentives for carriers. Transparency also supports passenger choice based on sustainability performance. Integration into policy allows regulators to detect early warning signs. Declining economic resilience scores may precede route withdrawals. Falling governance maturity may predict safety or compliance lapses. In the long run, regulators can tie ASPI to certification. High ASPI scores may accelerate approval for fleet expansion. Low scores could trigger additional audits or corrective plans.
9.2. Implications for Airlines
Airlines can embed ASPI into strategic decision-making processes. It provides a structured view of strengths and weaknesses. Environmental indicators help track progress towards emission reduction targets. Fuel burn per ASK informs fleet efficiency strategies. Social indicators support human capital and passenger experience management. Low complaint rates can be used in marketing narratives. High employee safety performance reduces accident-related costs and downtime. Governance maturity metrics help identify procedural and compliance gaps. Strength in SMS maturity can reduce insurance premiums. Strong green procurement scores may attract eco-conscious corporate clients. Economic resilience measures support revenue stability planning. Monitoring load factor volatility helps anticipate seasonal capacity adjustments. Ancillary revenue share informs diversification of income streams. ASPI can also guide route planning and network development. Carriers can prioritise routes with higher sustainability profitability potential. Low-carbon intensity routes may align with environmental branding strategies.
Fleet investment decisions can be aligned with ASPI performance gaps. Poor fuel efficiency scores may justify upgrading to newer aircraft. High SAF availability on certain routes can shape deployment choices. Airlines can use ASPI for competitive benchmarking within India. Tracking rivals’ environmental and social scores informs marketing positioning. Weak governance scores in competitors may signal market capture opportunities. Operational teams can integrate ASPI indicators into daily monitoring dashboards. This ensures sustainability remains a live operational priority. It moves performance management from annual review to continuous improvement. Linking ASPI scores to staff incentives may boost engagement. Cabin crew may be rewarded for improving passenger satisfaction. Ground staff may be recognised for reducing waste footprints.
ASPI can support communication with external stakeholders. Clear metrics make sustainability reports more credible and comparable. This can strengthen trust with passengers, regulators, and investors alike.
9.3. Implications for Investors
Investors can integrate ASPI scores into aviation credit assessments. Traditional credit ratings often neglect sustainability-related risks. ASPI adds non-financial indicators that predict long-term viability. Environmental performance can signal exposure to carbon pricing risks. Poor fuel efficiency may lead to higher operational costs. Low SAF adoption may attract regulatory penalties in the future. Social metrics indicate labour stability and service quality. High employee safety incidents may lead to operational disruptions. Poor passenger satisfaction may reduce brand loyalty and market share. Governance maturity reflects management discipline and compliance readiness. Low cybersecurity scores could signal exposure to costly breaches. Weak SMS maturity may increase insurance and financing costs. Economic resilience captures adaptability to market shocks. Stable load factors reduce revenue volatility during downturns. Diversified networks may lower exposure to regional disruptions. For equity investors, ASPI enables sustainability-adjusted valuation models. Airlines with improving ASPI scores may merit higher price multiples. Those with declining scores may face long-term value erosion. Fixed-income investors can use ASPI to assess bond risk. Airlines with low environmental scores may face refinancing challenges. Weak governance scores could increase default probability over time. Private equity can leverage ASPI in post-acquisition value creation. Sustainability performance improvements can increase exit valuation. It also aligns with global ESG investment mandates. ASPI-based rankings can influence investor relations strategies. High-scoring airlines can market themselves as sustainability leaders. This may improve access to green finance and lower borrowing costs.
9.4. Cross-Sector Benefits
Integration of ASPI into policy and strategy creates synergies. Regulators benefit from more precise and comparable sustainability data. Airlines gain a clear roadmap for operational improvement. Investors reduce risk through sustainability-adjusted decision-making. Collaborative use of ASPI can accelerate industry-wide decarbonisation. It creates a common language between stakeholders. Shared benchmarks encourage innovation and performance improvement. In the Indian context, ASPI supports national climate commitments. It aligns with India’s net-zero ambitions by 2070. It also fits within evolving global aviation sustainability frameworks.
10. Conclusions
This study developed the Aviation Sustainability Performance Index (ASPI India). It offers an integrated framework covering environmental, social, governance, and economic pillars. The index captures multidimensional performance in India’s commercial aviation sector. Using panel data, we examined airline performance from multiple perspectives. Descriptive statistics revealed variation across airlines and years. Factor analysis confirmed the robustness of the index structure. Panel fixed-effects models linked sustainability scores to operational stability. DiD analysis identified the impact of key policy shocks. The findings reveal clear policy and strategic insights. Regulators can use ASPI for compliance scoring and benchmarking. Airlines can apply ASPI for route planning and fleet investment. Investors can incorporate ASPI into credit and risk assessments. ASPI creates a shared measurement language for all stakeholders. It aligns incentives for environmental stewardship and operational resilience. It helps track progress toward India’s aviation decarbonisation goals. The study contributes methodologically by integrating multiple sustainability dimensions. It advances sector-specific ESG measurement tailored to emerging market contexts. It also offers a scalable framework for other developing countries. However, limitations remain in data granularity and scope. Future research should integrate real-time operational and emissions data. Expanding coverage to cargo and regional airlines is also important. Longitudinal tracking over decades can assess sustained policy impact. Overall, ASPI India is both practical and forward-looking. It can shape regulation, guide management, and inform investment. In doing so, it supports a more sustainable aviation industry.
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