Aerial mobile manipulation requires unmanned aerial vehicles (UAVs) to traverse heterogeneous environments such as indoor and outdoor domains, and connect navigation with subsequent physical interaction within the same trajectories. Existing aerial benchmarks are typically confined to single-environment settings, limiting evaluation of agents across continuous environmental transitions. When interaction is evaluated, agents are often initialized near the target, leaving the transition from navigation to interaction largely unassessed. This work introduces CrossFly, a benchmark for long-horizon interaction-oriented aerial mobility across heterogeneous environments. CrossFly contains 15K trajectories across more than 20 reconstructed scenes under a unified simulation and evaluation framework, covering Indoor, Outdoor, and Indoor↔Outdoor trajectories. It further introduces Interaction Readiness Rate (IRR) to assess whether terminal navigation states provide suitable conditions for downstream interaction without assuming a specific manipulation policy. Experiments with five representative aerial vision-language-action (VLA) agents and the proposed CrossFly-Agent show that Indoor↔Outdoor settings are more challenging than single-environment settings, with the highest success rate reaching 9.7% on unseen scenes. A downstream manipulation case study further validates the relevance of interaction-oriented arrival to subsequent physical interaction. We hope CrossFly helps advance aerial embodied intelligence toward unified mobility and physical interaction in heterogeneous environments.
Figures & tables
Figure 1: Overview of CrossFly benchmark. It focuses on interaction-oriented aerial mobility tasks and consists of a large dataset for unmanned aerial vehicle (UAV) imitation learning, featuring multiple aerial embodiments, heterogeneous environments, photorealistic rendering, and diverse target objects. To enable systematic experimental analysis under interaction-oriented mobility task settings, we additionally provide an evaluation protocol and propose an interaction readiness metric.
Figure 2: Trajectory statistics and scene diversity. (a) Distribution of scene types and task instructions with different numbers of subtasks (§ 3.1 ). (b) Distribution of trajectory lengths and path distances, summarizing the temporal and spatial scales of the dataset. (c) Representative environments in CrossFly , where each scene covers indoor and outdoor environments.
Dataset
Platform
Scene
Ntraj
Nscenes
Environment
Interaction
Dynamics
DoF
R2R ( Anderson et al., 2018 )
Ground Agent
Matterport3D
7,189
90
Indoor
✗
✗
Graph-based
VLN-CE ( Krantz et al., 2020 )
Ground Agent
Habitat
4,475
90
Indoor
✗
✗
2
OpenUAV ( Schmittle et al., 2018 )
UAV
AirSim + UE
12,149
22
Outdoor
✗
✓
6
AVDN ( Fan et al., 2023 )
UAV
xView
6,269
–
Outdoor
✗
✗
3
CityNav ( Lee et al., 2025 )
UAV
SensatUrban
32,637
34
Outdoor
✗
✗
4
Table 1: Comparison with related benchmarks (§ 3.1 ).
Figure 3: Overview of the dataset construction pipeline (§ 3.2 ). CrossFly begins with reconstructed scenes from point clouds and realistic rendering, followed by waypoint annotation and trajectory acquisition through UAV simulation. The collected trajectories are then assembled with RGB observations, UAV states, and task-related annotations to construct the benchmark dataset.
Figure 4: Architecture of CrossFly-Agent (§ 4.1 ) . A high-level VLM planner uses visual context spanning the observed trajectory to predict the active language subtask. Conditioned on this subtask, a low-level VLA policy combines the initial observation with recent visual context to generate flight action chunks and determine when to predict a manipulation-invocation signal.
Indoor
Outdoor
Indoor ↔ Outdoor
Model
NE ↓
SR ↑
OSR ↑
IRR ↑
NE ↓
SR ↑
OSR ↑
IRR ↑
NE ↓
SR ↑
OSR ↑
IRR ↑
π0 ( Black et al., 2024 )
4.07
17.7
23.6
37.2
3.79
20.4
27.8
37.0
7.21
13.2
19.7
29.1
π0 -FAST ( Pertsch et al., 2025 )
3.81
18.5
19.2
39.0
3.42
22.7
30.1
38.9
6.63
15.8
22.1
30.7
OpenFly-Agent ( Gao et al., 2026 )
3.48
15.1
21.4
46.7
3.39
18.1
20.6
43.4
5.93
13.9
17.7
34.2
OpenVLA-OFT ( Kim et al., 2025 )
3.84
17.2
21.7
47.9
3.51
19.5
24.4
38.1
6.87
14.9
21.3
38.8
Table 2: Quantitative comparison on seen scenes (§ 4.2 ).
Indoor
Outdoor
Indoor ↔ Outdoor
Model
NE ↓
SR ↑
OSR ↑
IRR ↑
NE ↓
SR ↑
OSR ↑
IRR ↑
NE ↓
SR ↑
OSR ↑
IRR ↑
π0 ( Black et al., 2024 )
5.72
10.8
13.4
26.7
5.26
13.5
15.8
27.8
9.38
2.4
4.1
21.7
π0 -FAST ( Pertsch et al., 2025 )
5.18
13.2
15.7
28.4
4.83
15.6
17.2
29.1
8.74
3.7
6.3
25.2
OpenFly-Agent ( Gao et al., 2026 )
4.49
10.6
13.9
32.7
4.22
13.4
15.1
26.4
7.61
7.2
7.9
26.2
OpenVLA-OFT ( Kim et al., 2025 )
5.45
11.9
14.6
27.5
4.97
14.1
16.4
28.2
9.02
3.1
4.7
27.9
Table 3: Quantitative comparison on unseen scenes (§ 4.2 ).
Figure 5: Qualitative results of CrossFly-Agent (§ 4.3 ). This example shows the instruction and selected third-person views. Blue text denotes navigation actions, while red text denotes manipulation actions. The top row shows the trajectory from the start to the interaction-ready state, while the bottom row covers the trajectory from the interaction-ready state to task completion.
Task Suite
Traj. Length
# Subtasks
Instr. Length
NE ↓
SR ↑
Indoor
11.2
6.8
18.9
4.15
23.64
Outdoor
11.8
6.7
18.5
4.36
25.28
Indoor ↔ Outdoor
11.5
6.8
18.8
6.43
10.98
Table 4: Performance comparison under matched trajectories.
Figure 6: Manipulation case study (§ 4.4 ). Each row represents a manipulation case. The leftmost image shows the initial observation of UAV. The top case satisfies IRR criteria and achieves a successful grasp, whereas the bottom case violates IRR criteria and fails to grasp.
Appendix figures & tables4 assets
Supplementary material from the paper’s appendix.
Appendix
Figure 7: Qualitative results of CrossFly-Agent .
Figure 8: Failure case. Sometimes, UAV collides with obstacles when traversing passages across indoor–outdoor boundaries, indicating that navigation in transition regions remains challenging.
Split
# Scenes
Scene overlap with training
Used for training
Training
18
–
Yes
Seen
18
Same scenes
No
Unseen
5
None
No
Appendix
Table 5: Scene-level partition used in CrossFly (§ B.1 ).